Copyright 1995, Institute for Scientific Information Inc.

Database : Science Citation Index

(18 other papers mostly on computed tomography (CT, PET, SPECT)

(19)  TI: PERFORMANCE OF A BAF2-TMAE PROTOTYPE DETECTOR FOR USE IN PET
      AU: WELLS_K, VISVIKIS_D, OTT_RJ, ZWEIT_J, BATEMAN_JE, STEPHENSON_R, 
          CONNOLLY_J, TAPPERN_G
      NA: ROYAL MARSDEN HOSP,INST CANC RES,DEPT PHYS,BELMONT SM2 
          5PT,SURREY,ENGLAND
          RUTHERFORD APPLETON LAB,DIDCOT,OXON,ENGLAND
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt2 
          pp.2737-2742
      AB: A BaF2-TMAE detector has been developed for use in positron 
          emission tomography (PET). The detector achieves an efficiency of 
          23.5%, a time resolution of 3.5ns FWHM, and a spatial resolution 
          of 6.0mm FWHM with no change in the normal operating parameters. 
          The only deterioration observed in a typical working day is a 
          small increase in the FWTM of the time resolution. This paper 
          describes how this level of performance was achieved and also how 
          these results have been used as the basis for the design of a 
          large area positron camera.
      KP: POSITRON CAMERA, CHAMBER

(20)  TI: EXPERIMENTAL-VERIFICATION OF BREMSSTRAHLUNG PRODUCTION AND 
          DOSIMETRY PREDICTIONS AS A FUNCTION OF ENERGY AND ANGLE
      AU: BEUTLER_DE, HALBLEIB_JA, SANFORD_TWL, KNOTT_DP
      NA: SANDIA NATL LABS,ALBUQUERQUE,NM,87185
          TECH SUPPORT CORP,ALBUQUERQUE,NM,87185
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt2 
          pp.2727-2736
      AB: Measurements of energy deposition from bremsstrahlung production 
          as a function of angle and beam energy (5-25 MeV) are shown to be 
          in excellent agreement with Monte Carlo predictions. Dosimetry 
          measurements are made and predicted in both equilibrated and 
          underequilibrated radiation environments. In the latter ease the 
          quality of the agreement requires an accurate prediction of both 
          the photon and electron spectra produced by the primary electron 
          beam. An improved empirical equation for predicting 
          bremsstrahlung production is also presented. This empirical 
          relation can be used to estimate doses without resorting to 
          expensive calculational efforts, It also gives an analytical 
          relationship for dose as a function of energy and angle for a 
          converter optimized for bremsstrahlung production using 15.5 MeV 
          electrons.
      KP: MEV ELECTRONS

(21)  TI: EFFECT OF NEUTRON-IRRADIATION ON THE BREAKDOWN VOLTAGE OF POWER 
          MOSFETS
      AU: HASAN_SMY, KOSIER_SL, SCHRIMPF_RD, GALLOWAY_KF
      NA: UNIV ARIZONA,DEPT ELECT & COMP ENGN,TUCSON,AZ,85721
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt2 
          pp.2719-2726
      AB: The effect of neutron irradiation on power 
          metal-oxide-semiconductor field effect transistor (power MOSFET) 
          breakdown voltage has been investigated. Transistors with various 
          breakdown voltage ratings were irradiated in a TRIGA nuclear 
          reactor with cumulative fluence levels up to 5 X 10(14) neutrons 
          / cm(2) (1 MeV equivalent). Noticeable increases in the breakdown 
          voltages are observed in p-type MOSFET's after 10(13) neutrons / 
          cm(2) and in p-type MOSFETs after 10(12) neutrons / cm(2). An 
          increase in breakdown voltage of as much as 30% is observed after 
          5 X 10(14) neutrons / cm(2). The increase in breakdown voltage is 
          attributed to the neutron-irradiation-induced defects which 
          decrease the mean free path and trap majority carriers in the 
          space charge region. The effect of positive trapped oxide charge 
          due to concomitant gamma radiation and the effect of the 
          termination structure on the increase in breakdown voltage are 
          considered. An empirical model is presented to predict the value 
          of the breakdown voltage as a function of neutron fluence.
      KP: IONIZING-RADIATION

(22)  TI: TLBRXI1-X PHOTODETECTORS FOR SCINTILLATION SPECTROSCOPY
      AU: SHAH_KS, LUND_JC, OLSCHNER_F, ZHANG_J, MOY_LP, SQUILLANTE_MR, 
          MOSES_WW, DERENZO_SE
      NA: RADIAT MONITORING DEVICES INC,WATERTOWN,MA,02172
          UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA,94720
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt2 
          pp.2715-2718
      AB: This paper reports on the evaluation of photodetectors fabricated 
          from a ternary semiconductor, TlBrxI1-x for application in 
          scintillation spectroscopy. These photodetectors are 
          characterized in terms of their resistivity, charge transport 
          parameters, quantum efficiency as a function of wavelength, and 
          finally their performance as scintillation spectrometers. The 
          details about TlBrxI1-x purification, crystal growth and device 
          fabrication are also addressed.
      KP: DETECTORS

(23)  TI: SINGLE EVENT EFFECTS AND PERFORMANCE PREDICTIONS FOR SPACE 
          APPLICATIONS OF RISC PROCESSORS
      AU: KIMBROUGH_JR, COLELLA_NJ, DENTON_SM, SHAEFFER_DL, SHIH_D, 
          WILBURN_JW, COAKLEY_PG, CASTENEDA_C, KOGA_R, CLARK_DA, ULLMANN_JL
      NA: LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA,94550
          JAYCOR,SAN DIEGO,CA,92121
          CROCKER NUCL LAB,DAVIS,CA,95616
          AEROSP CORP,EL SEGUNDO,CA,90245
          LOS ALAMOS NATL LAB,LOS ALAMOS,NM,87545
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt2 
          pp.2706-2714
      AB: Proton and ion Single Event Phenomena (SEP) tests were performed 
          on 32-b processors including R3000A's from all commercial 
          manufacturers along with the Performance PR3400 family, 
          Integrated Device Technology Inc. 79R3081, LSI Logic Corporation 
          LR33000HC, and Intel i80960MX parts. The microprocessors had 
          acceptable upset rates for operation in a low earth orbit or a 
          lunar mission such as CLEMENTINE with a wide range in proton 
          total dose failure. Even though R3000A devices are 60% smaller in 
          physical area than R3000 devices, there was a 340% increase in 
          device Single Event Upset (SEU) cross section. Software tests of 
          varying complexity demonstrate that registers and other 
          functional blocks using register architecture dominate the cross 
          section. The current approach of giving a single upset cross 
          section can lead to erroneous upset rates depending on the 
          application software.
      KP: SEU, UPSETS, ORBIT

(24)  TI: CORRECTED MULTIPLE UPSETS AND BIT REVERSALS FOR IMPROVED 1-S 
          RESOLUTION MEASUREMENTS
      AU: BRUCKER_GJ, STASSINOPOULOS_EG, STAUFFER_CA
      NA: NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD,20771
          SES,GREENBELT,MD
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt2 
          pp.2698-2705
      AB: Previous work has studied the generation of single and multiple 
          errors in control and irradiated static RAM samples (Harris 
          6504RH) which were exposed to heavy ions for relatively long 
          intervals of time (minute), and read out only after the beam was 
          shut off. The present investigation involved storing 4k X 1 bit 
          maps every second during 1 min ion exposures at low flux rates of 
          10(3) ions/cm(2)-s in order to reduce the chance of two 
          sequential ions upsetting adjacent bits. The data were analyzed 
          for the presence of adjacent upset bit locations in the physical 
          memory plane, which were previously defined to constitute 
          multiple upsets. Improvement in the time resolution of these 
          measurements has provided more accurate estimates of multiple 
          upsets. The results indicate that the percentage of multiples 
          decreased from a high of 17% in the previous experiment to less 
          than 1% for this new experimental technique. Consecutive double 
          and triple upsets (reversals of bits) were detected. These were 
          caused by sequential ions hitting the same bit, with one or two 
          reversals of state occurring in a 1-min run. In addition to these 
          results, a status review for these same parts covering 3.5 years 
          of imprint damage recovery is also presented.

(25)  TI: CONSIDERATIONS IN THE CONTROL OF PWR-TYPE MULTIMODULAR REACTOR 
          PLANTS
      AU: KIM_KK, BERNARD_JA
      NA: KOREA ATOM ENERGY RES INST,TAEJON 305600,SOUTH KOREA
          MIT,NUCL REACTOR LAB,CAMBRIDGE,MA,02139
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt2 
          pp.2686-2697
      AB: Issues in the control of PWR-type multimodular reactor plants are 
          discussed with emphasis on the need for operation under 
          conditions of unbalanced loads, operating strategies for both 
          single- and multireactor systems, and the coordinated adjustment 
          of power and temperature. One defining characteristic of a 
          multimodular plant is that each unit will probably be loaded 
          differently so as to compensate for the effects of varying 
          maintenance outages and, if desired, to stagger refuelings. A 
          second characteristic is interdependency in that, with several 
          reactors connected to a common turbine, a change in any one unit 
          will propagate to the others. The combination of these two 
          factors makes operation of a multimodular plant differ from that 
          of existing single-reactor ones. For example, conventional 
          sliding-T-ave load maps cannot be applied directly to a 
          multimodular system because, with the exception of the 
          highest-powered unit, each reactor's temperature will be a 
          function of not only its power level but also that of the most 
          heavily loaded one. Similarly, withdrawal of the control rods in 
          a fully loaded PWR will, in the presence of a large negative 
          temperature coefficient, cause hot and cold leg temperatures to 
          rise but leave power and core Delta T unchanged. In a 
          multimodular system, there will be a shift in power to the 
          affected reactor. These and other differences in the behavior of 
          multimodular and single-reactor systems are delineated. The paper 
          concludes with some practical suggestions on the operation of 
          PWR-type multimodular plants.

(26)  TI: A NEW APPROACH TO CONTROL OF XENON SPATIAL OSCILLATION DURING 
          LOAD FOLLOW OPERATION VIA ROBUST SERVO SYSTEMS
      AU: UKAI_H, IWAZUMI_T
      NA: NAGOYA INST TECHNOL,DEPT ELECT & COMP ENGN,SHOWA KU,GOKISO 
          CHO,NAGOYA,AICHI 466,JAPAN
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt2 
          pp.2675-2685
      AB: The control problem of xenon-induced spatial oscillations of PWR 
          in the axial direction during a load following operation is 
          investigated. The system models are described by a one-group 
          diffusion equation with xenon and temperature feedbacks, iodine 
          and xenon dynamic equations, and heat conduction processes. 
          Control is implemented by the full-length and the part-length 
          control rods and the boron concentration. In order to achieve the 
          control purpose, control models are formulated as the design 
          problem of robust servo systems for distributed parameter reactor 
          systems. The total thermal power and the axial offset are chosen 
          as outputs to be controlled. The control systems consist of servo 
          compensators and stabilizing compensators. They are designed 
          based on the finite-dimensional systems which are constructed by 
          linearizing around steady states, approximating by the Galerkin 
          method, and reducing dimensions via the singular perturbation 
          method. A new and simple computational algorithm to obtain an 
          approximate solution of a steady-state neutron balance is 
          developed via the perturbation method. Some results of numerical 
          simulations are shown in order to discuss the effectiveness of 
          the theory developed in this paper. In particular, it is shown 
          that the designed servo systems are robust against model errors 
          with linearization and modal truncation.
      KP: DISTRIBUTED PARAMETER-SYSTEMS, FLUX

(27)  TI: A MEASUREMENT OF THE FIRST TOWNSEND COEFFICIENT AS A FUNCTION OF 
          THE ELECTRIC-FIELD FOR A TMAE-HE MIXTURE
      AU: SHUPING_Z, BRUYNDONCKX_P, GOLDBERG_M, TAVERNIER_S
      NA: FREE UNIV BRUSSELS,INTERUNIV INST HIGH ENERGIES,PLEINLAAN 
          2,B-1050 BRUSSELS,BELGIUM
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt2 
          pp.2671-2674
      AB: TMAE (tetrakis-dimethylamino-ethylene) has been widely used in 
          photo-ionization detectors in the last decade. As a gas 
          photocathode, it has one of the lowest ionization potentials of 
          the organic compounds studied to date, a high quantum efficiency, 
          and adequate vapor pressures at just above room temperatures. In 
          order to understand the gas amplification mechanism of an 
          avalanche chamber filled with a TMAE-based gas mixture operated 
          at a low gas pressure, we have measured the first Townsend 
          coefficient for a TMAE-He mixture with a parallel plate avalanche 
          chamber. Based on this result, the gas amplification process in 
          wire chambers operated at low gas pressure is discussed.

(28)  TI: RADIATION EFFECTS RESEARCH IN THE 60S
      AU: CONRAD_EE
      NA: 7500 MARBURY RD,BETHESDA,MD,20817
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2648-2659
      AB: This talk provides a review of some of the significant issues and 
          advances in nuclear radiation effects that took place in the 
          1960's. The subjects include neutron induced displacement damage 
          in semiconductors and ionization effects in semiconductor and 
          dielectric materials and piece-parts. The relationship between 
          the basic mechanisms and the radiation response of components in 
          the areas of TREE, SGEMP, and thermomechanical effects will be 
          described to show how the necessity for understanding and 
          modeling was driven by the requirements for radiation hardened 
          electronic systems. The accomplishments will be described within 
          the context of a changing atmosphere of;
          International politics,
          The demise of atmospheric testing and the birth and evolution of 
          the underground nuclear effects test,
          The evolution of above ground laboratory test facilities and
          The eccentricities and passions of some of the people in the 
          business.

(29)  TI: SATURATION OF THE DOSE-RATE RESPONSE OF BIPOLAR-TRANSISTORS BELOW 
          10-RAD(SIO2)/S - IMPLICATIONS FOR HARDNESS ASSURANCE
      AU: NOWLIN_RN, FLEETWOOD_DM, SCHRIMPF_RD
      NA: USAF,PHILLIPS LAB,MICROELECTR & PHOTON RES 
          BRANCH,ALBUQUERQUE,NM,87117
          SANDIA NATL LABS,DEPT 1332,ALBUQUERQUE,NM,87185
          UNIV ARIZONA,DEPT ELECT & COMP ENGN,TUCSON,AZ,85721
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2637-2641
      AB: The gain degradation of modern bipolar transistors was 
          investigated for dose rates ranging from 0.01 similar to 2000 
          rad(SiO2)/s; Five different radiation sources were used for the 
          exposures: three Co-60 sources, a 10-keV x-ray source, and a 
          Cs-137, source. The C-137 exposures at 0.01 rad(SiO2)/s are two 
          orders of magnitude lower in dose rate than any previous 
          irradiations for this process and thus facilitate comparison to 
          the device response in space. Low-dose-rate gain degradation 
          exceeds high-dose-rate degradation for total doses less than 1 
          Mrad(SiO2), consistent with previous reports. For the first time, 
          the gain degradation is demonstrated to be equivalent for dose 
          rates between 0.01 and 10 rad(SiO2)/s, suggesting that the 
          dose-rate response saturates at similar to 10 rad(SiO2)/s for the 
          devices studied in this work. On the basis of a recent model, 
          high-dose-rate irradiations at 60 degrees C were performed and 
          found to be consistent with the room-temperature, low-dose-rate, 
          saturated response. These results suggest several promising new 
          approaches to bipolar space-qualification testing.
      KP: X-RAY, CO-60 IRRADIATIONS

(30)  TI: THE IMPROVEMENT OF MOSFET PREDICTION IN-SPACE ENVIRONMENTS USING 
          THE CONVERSION MODEL
      AU: SHVETZOVSHILOVSKY_IN, CHEREPKO_SV, PERSHENKOV_VS
      NA: MOSCOW ENGN PHYS INST,MOSCOW 115409,RUSSIA
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2631-2636
      AB: The modeling of MOS device response to a low dose rate 
          irradiation has been performed. The existing conversion model 
          based on the linear dependence between positive oxide charge 
          annealing and interface trap buildup accurately predicts the long 
          time response of MOSFETs with relatively thick oxides but 
          overestimates the threshold voltage shift for radiation hardened 
          MOSFETs with thin oxides. To give an explanation to this fact, we 
          investigate the impulse response function for threshold voltage. 
          A revised model, which incorporates the different energy levels 
          of hole traps in the oxide improves the fit between the model and 
          data and gives an explanation to the fitting parameters 
          dependence on oxide field.
      KP: TRAPPED HOLES, DEVICES

(31)  TI: RADIATION EFFECTS BEFORE 1960
      AU: VANLINT_V
      NA: 1032 SKYLARK DR,LA JOLLA,CA,92037
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2642-2647

(32)  TI: A COMPLETE RADIATION RELIABILITY SOFTWARE SIMULATOR
      AU: PAVAN_P, TU_RH, MINAMI_ER, LUM_G, KO_PK, HU_CH
      NA: UNIV MODENA,DIPARTIMENTO SCI INGN,VIA CAMPI 213-B,I-41100 
          MODENA,ITALY
          UNIV CALIF BERKELEY,DEPT ELECT ENGN & COMP SCI,BERKELEY,CA,94720
          LOCKHEED MISSILES & SPACE CO,SUNNYVALE,CA,94088
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2619-2630
      AB: In this paper we describe a simulator which can be used to study 
          the effects on circuit behavior of two radiation phenomena: 
          Single Event Upset (SEU) and total-dose radiation effects. Using 
          this simulator the user can predict the error rate in large 
          circuits due to single event upset. The error rate model 
          described here uses a well established methodology, but for the 
          first time a different choice is made on picking up the sensitive 
          nodes, enabling a quick prediction even for very complex 
          circuits. The simulator predicts circuit behavior after 
          total-dose irradiation using as inputs: the dose rate and the 
          total dose, parameter sets that characterize-the transistor 
          response to radiation, and the circuit netlist. The total-dose 
          simulator is based on physical models of the changes in the 
          MOSFET caused by radiation. We quantify the degradation of each 
          MOSFET in a circuit with two parameters and determine the change 
          in the MOSFET characteristics from preirradiation MOSFET data. 
          Using the ''irradiated'' MOSFET parameters, we can simulate 
          circuit behavior using an ordinary circuit simulator such as 
          SPICE. With this simulator, one can study how resistant a circuit 
          is to changes due to irradiation and design circuits to be 
          functionally radiation ''hard''. The ''double-kink'' in the 
          MOSFET subthreshold region due to the parasitic effect of the 
          edge transistors can be simulated and the user is advised when 
          leakage current unacceptably large. The speed degradation of a 
          ring oscillator was simulated and the results compared with 
          actual measured data.
      KP: TOTAL-DOSE RADIATION, CMOS VLSI CIRCUITS, MOS DEVICES, 
          INTEGRATED-CIRCUITS, TRANSISTORS, LEAKAGE, MODEL, BIAS

(33)  TI: RADIATION EFFECTS R-AND-D IN THE 1970S - A RETROSPECTIVE VIEW
      AU: SROUR_JR
      NA: NORTHROP GRUMMAN CORP,HAWTHORNE,CA,90251
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2660-2665
      AB: This paper provides a retrospective view of radiation effects 
          research and development in the 1970s, with emphasis placed on 
          advances made in four areas: single event effects; MOS devices; 
          charge-coupled devices; and displacement damage. Lessons learned 
          and future opportunities are considered.
      KP: SILICON DEPLETION REGIONS, INTERFACE-STATE BUILDUP, 
          INDUCED SOFT ERRORS, MOS CAPACITORS, HOLE TRANSPORT, 
          SEMICONDUCTOR-DEVICES, DAMAGE, SIO2, SIO2-FILMS, GENERATION

(34)  TI: MAPPING CMOS RADIATION TOLERANCE DATA ON A 4-LANE CHART
      AU: HOLMESSIEDLE_A, ADAMS_L
      NA: BRUNEL UNIV,CTR RADIAT DAMAGE STUDIES,UXBRIDGE UB8 
          3PH,MIDDX,ENGLAND
          EUROPEAN SPACE AGCY,ESTEC,2200 AG NOORDWIJK,NETHERLANDS
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2613-2618
      AB: An analysis is made of the growth of threshold voltage as a 
          function of radiation dose in a very wide range of Complementary 
          Metal-Oxide Semiconductor (CMOS) devices, all the way from low 
          (kilorad) to very high (gigarad) doses. It is found that such 
          results can be organized into four LANES OR CORRIDORS on the 
          growth curve diagram. The resulting FOUR-LANE CLASSIFICATION is 
          useful in selecting CMOS technologies and offers a new 
          terminology for describing the radiation tolerance of ICs, namely 
          ''Old Soft, New Soft, Tolerant and Very Tolerant''. The form of 
          the lanes, though arrived at empirically, is consistent with the 
          current theory of radiation response of MOS structures. The 
          position of a device test result in this framework is a useful 
          indication of the suitability of a device for use in a given 
          radiation environment and could form the basis of a ''league 
          table'', used to assess the performance of ''hardening 
          laboratories'' around the world and as a reference source for the 
          properties of thin-film oxide materials.
      KP: MOS, TRANSISTORS, HARDNESS, DEVICES

(35)  TI: TOTAL-DOSE CORRELATION OF 4007 DEVICES FLOWN ON THE CRRES MEP 
          EXPERIMENT
      AU: ZIMMERMAN_DM, RAY_KP
      NA: MAXWELL LABS INC,DIV S CUBED,SAN DIEGO,CA,92123
          PHILLIPS LAB,GPSP,BEDFORD,MA,01731
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2605-2612
      AB: This paper considers total dose measurements of six 4007 type 
          devices in the Microelectronics Package (MEP) on board the 
          Combined Release and Radiation Effects Satellite (CRRES). The 
          on-orbit device performance of the 4007 devices is compared to 
          Co-60 ground test data from identical devices. The results show 
          that the low dose rate space data and the higher dose rate Co-60 
          data agree within a factor of 2.5 for all six 4007 device types.
      KP: CMOS

(36)  TI: EFFECT OF TEST METHOD ON THE FAILURE DOSE OF SEEQ 28C256 EEPROM
      AU: VERKASALO_R
      NA: NOKIA MOBILE PHONES,POB 50,SF-90571 OULU,FINLAND
          VTT ELECTR,SF-90571 OULU,FINLAND
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2600-2604
      AB: Two lots of SEEQ 28C256 EEPROM were tested for total dose 
          tolerance. Differences between them were found to result in a 
          dependence of the relative superiority and failure doses of the 
          two lots on the test method and the failure criterion. The 
          failure doses were between 6 and 15 krad, and the failure 
          mechanisms were an increase in the standby current and a loss of 
          programmability.

(37)  TI: FAST SWITCHED-BIAS ANNEALING OF RADIATION-INDUCED OXIDE-TRAPPED 
          CHARGE AND ITS APPLICATION FOR TESTING OF RADIATION EFFECTS IN 
          MOS STRUCTURES
      AU: PERSHENKOV_VS, BELYAKOV_VV, SHALNOV_AV
      NA: MOSCOW ENGN PHYS INST,MOSCOW 115409,RUSSIA
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2593-2599
      AB: A method for low-dose-rate MOS device response testing is 
          presented and verified. The test technique is based on the use of 
          a special switched-bias irradiation with subsequent positive and 
          negative pulses. The negative bias pulses provide nearly complete 
          annealing of the oxide charge trapped during the positive bias 
          pulses. As a result, after a series of positive/negative cycles 
          the value of oxide-trapped charge does not change significantly 
          but the interface charge increases. The advantages, limitations 
          and applications of this test technique are described.
      KP: SILICON DIOXIDE, INTERFACE, DEVICES, BUILDUP, CMOS, IRRADIATIONS, 
          HOLES, RAY

(38)  TI: CRITICAL-EVALUATION OF THE PULSED-LASER METHOD FOR SINGLE EVENT 
          EFFECTS TESTING AND FUNDAMENTAL-STUDIES
      AU: MELINGER_JS, BUCHNER_S, MCMORROW_D, STAPOR_WJ, WEATHERFORD_TR, 
          CAMPBELL_AB
      NA: USN,RES LAB,CODE 6613,WASHINGTON,DC,20375
          USA,RES LAB,ADELPHI,MD,20783
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2574-2584
      AB: In this paper we present an evaluation of the pulsed laser as a 
          technique for single events effects (SEE) testing. We explore in 
          detail the important optical effects, such as laser beam 
          propagation, surface reflection, and linear and nonlinear 
          absorption, which determine the nature of laser-generated charge 
          tracks in semiconductor materials. While there are differences in 
          the structure of laser- and ion-generated charge tracks, we show 
          that in many cases the pulsed laser remains an invaluable tool 
          for SEE testing. Indeed, for several SEE applications, we show 
          that the pulsed laser method represents a more practical approach 
          than conventional accelerator-based methods.
      KP: INDUCED CHARGE COLLECTION, GAAS-MESFETS, SEU

(39)  TI: COMPARISON OF HOT-CARRIER AND RADIATION-INDUCED INCREASES IN BASE 
          CURRENT IN BIPOLAR-TRANSISTORS
      AU: PEASE_RL, KOSIER_SL, SCHRIMPF_RD, COMBS_WE, DAVEY_M, DELAUS_M, 
          FLEETWOOD_DM
      NA: RLP RES,ALBUQUERQUE,NM
          UNIV ARIZONA,TUCSON,AZ
          USN,CTR SURFACE WARFARE,CRANE,IN
          SANDIA NATL LABS,ALBUQUERQUE,NM,87185
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2567-2573
      AB: A comparison was made between hot-carrier-stress induced and 
          ionizing-radiation induced increases in the base current of 
          bipolar linear microcircuit transistors from two process 
          technologies. The comparison was made on the basis of a failure 
          stress in seconds and a failure dose in rad(SiO2) for a failure 
          criterion of Delta I-B = 2 nA measured at an I-C of 1 mu A and 
          V-CE of 5 V. Comparisons were made for several die on a single 
          wafer, die from different wafers in a process lot, and die from 
          split lots with various base oxide (also called spacer or screen 
          oxide) hardening techniques applied. For each of these cases no 
          correlation was found between stress-induced failure and 
          ionizing-radiation induced failure. This result is consistent 
          with modeling that shows different mechanisms for the degradation 
          from hot-carriers and ionization. Hot-carrier stress induced 
          damage is dominated by interface traps near the emitter-base 
          junction periphery; whereas, ionizing-radiation induced damage is 
          dominated by trapped positive charge in the base oxide over the 
          extrinsic-base region.
      KP: DEVICES

(40)  TI: A METHODOLOGY FOR THE IDENTIFICATION OF WORST-CASE TEST VECTORS 
          FOR LOGICAL FAULTS INDUCED IN CMOS CIRCUITS BY TOTAL-DOSE
      AU: ABOUAUF_AA, BARBE_DF, EISEN_HA
      NA: USA,RES LAB,2800 POWDER MILL RD,ADELPHI,MD,20783
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2585-2592
      AB: A new methodology was developed for the identification of the 
          worst-case combination of irradiation and postirradiation test 
          vectors. The methodology significantly simplifies total-dose 
          testing of CMOS VLSI devices. It also provides more accurate 
          assessment of failure levels for such devices.
      KP: VLSI CIRCUITS, SIMULATION

(41)  TI: EVALUATION OF A METHOD FOR ESTIMATING LOW-DOSE-RATE IRRADIATION 
          RESPONSE OF MOSFETS
      AU: KHOSROPOUR_P, FLEETWOOD_DM, GALLOWAY_KF, SCHRIMPF_RD, CALVEL_P
      NA: UNIV ARIZONA,DEPT ELECT & COMP ENGN,TUCSON,AZ,85721
          SANDIA NATL LABS,ALBUQUERQUE,NM,87185
          ALCATEL ESPACE,TOULOUSE,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2560-2566
      AB: A simple method for estimating the threshold-voltage shift due to 
          low-dose-rate ionizing irradiation was recently proposed for 
          power MOSFETs. In this work, the physical considerations 
          governing the applicability of the method are examined. In 
          addition to the power MOSFETs discussed in the previous paper, 
          the method is applied to integrated MOSFETs from two different 
          technologies and critically evaluated. For this method to work, 
          the oxide trapped charge due to low-dose-rate irradiation should 
          be the same as that following irradiation at the dose rates 
          specified in MIL-STD-883D Method 1019.4, and the interface-trap 
          density following low-dose-rate irradiation should be the same as 
          that following irradiation at 1019.4 rates and subsequent 
          high-temperature annealing. Of the mio integrated technologies 
          evaluated, the method correctly predicts the low-dose-rate 
          threshold-voltage shift for one, but not for the other. In the 
          case where the method yields the correct result, the agreement 
          appears to be coincidental. The results, coupled with the 
          necessity for transistor-level test structures, suggests that the 
          proposed method is applicable primarily to power MOSFETs that 
          exhibit slow annealing of oxide-trapped charge and no rebound 
          during low-dose-rate irradiation.
      KP: HARDNESS ASSURANCE, SPACE ENVIRONMENTS, INTERFACE TRAPS, 
          BORDER TRAPS, MOS DEVICES, MECHANISMS

(42)  TI: EFFECTS OF BURN-IN ON RADIATION HARDNESS
      AU: SHANEYFELT_MR, FLEETWOOD_DM, SCHWANK_JR, MEISENHEIMER_TL, 
          WINOKUR_PS
      NA: SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM,87185
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2550-2559
      AB: Transistors and ICs were irradiated with or without 
          pre-irradiation elevated-temperature biased stresses (i.e., 
          burn-in). These stresses lead to larger radiation-induced 
          transistor threshold-voltage shifts and increases in IC static 
          power supply leakage current (two orders of; magnitude) in 
          stressed ICs than for ICs not subjected to a stress. In addition, 
          these stresses led to reduced degradation in timing parameters. 
          The major cause of the differences is less radiation-induced 
          interface-trap buildup for transistors subjected to an 
          elevated-temperature biased stress. These results were observed 
          for two distinctly different technologies and have significant 
          implications on hardness assurance testing. One could 
          significantly (1) overestimate degradation in timing parameters 
          resulting in the rejection of acceptable ICs and increased system 
          cost, or (2) underestimate the increase in static supply leakage 
          current of ICs leading to system failure. These results suggest 
          that radiation qualification testing must be performed on 
          integrated circuits that have been subjected to all 
          high-temperature biased stresses experienced in normal production 
          flow or system use.
      KP: MOS DEVICES, ASSURANCE, TRANSISTORS, ICS

(43)  TI: DEPENDENCE OF TOTAL-DOSE RESPONSE OF BIPOLAR LINEAR MICROCIRCUITS 
          ON APPLIED DOSE-RATE
      AU: MCCLURE_S, PEASE_RL, WILL_W, PERRY_G
      NA: HUGHES SPACE & COMMUN CO,LOS ANGELES,CA,90009
          BOEING CO,DEF & SPACE GRP,SEATTLE,WA,98124
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2544-2549
      AB: The effect of dose rate on the total dose radiation hardness of 
          three commercial bipolar linear microcircuits is investigated. 
          Total dose tests of linear bipolar microcircuits show larger 
          degradation at 0.167 rad/s than at 90 rad/s even after the high 
          dose rate test is followed by a room temperature plus a 100 
          degrees C anneal. No systematic correlation could be found for 
          degradation at low dose rate versus high dose rate and anneal. 
          Comparison of the low dose rate with the high dose rate anneal 
          data indicates that MIL-STD-883, Method 1019.4 is not a 
          worst-case test method when applied to bipolar microcircuits for 
          low dose rate space applications.

(44)  TI: HARDNESS VARIABILITY IN COMMERCIAL TECHNOLOGIES
      AU: SHANEYFELT_MR, WINOKUR_PS, MEISENHEIMER_TL, SEXTON_FW, ROESKE_SB, 
          KNOLL_MG
      NA: SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM,87185
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2536-2543
      AB: The radiation hardness of commercial Floating Gate 256K E(2)PROMs 
          from a single diffusion lot was observed to vary between 5 to 25 
          krad(Si) when irradiated at a low dose rate of 64 mrad(Si)/s. 
          Additional variations in E(2)PROM hardness were found to depend 
          on bias condition and failure mode (i.e., inability to read or 
          write the memory), as well as the foundry at which the part was 
          manufactured. This variability is related to system requirements, 
          and it is shown that hardness level and variability affect the 
          allowable mode of operation for E(2)PROMs in space applications. 
          The radiation hardness of commercial 1-Mbit CMOS SRAMs from 
          Micron, Hitachi, and Sony irradiated at 147 rad(Si)/s was 
          approximately 12, 13, and 19 krad(Si), respectively. These 
          failure levels appear to be related to increases in leakage 
          current during irradiation. Hardness of SRAMs from each 
          manufacturer varied by less than 20%, but differences between 
          manufacturers are significant. The Qualified Manufacturer's List 
          approach to radiation hardness assurance is suggested as a way to 
          reduce variability and to improve the hardness level of 
          commercial technologies.
      KP: CMOS, ENVIRONMENTS, ASSURANCE, IRRADIATION, TRANSISTORS, 
          DEPENDENCE, ICS

(45)  TI: THE EFFECTS OF IONIZING-RADIATION ON COMMERCIAL POWER MOSFETS 
          OPERATED AT CRYOGENIC TEMPERATURES
      AU: JOHNSON_GH, KEMP_WT, SCHRIMPF_RD, GALLOWAY_KF, ACKERMANN_MR, 
          PUGH_RD
      NA: USAF,PHILLIPS LAB,MICROELECTR & PHOTON GRP,KIRTLAND AFB,NM,87117
          UNIV ARIZONA,DEPT ELECT & COMP ENGN,TUCSON,AZ,85721
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2530-2535
      AB: This is the first report of commercial n- and p-channel power 
          MOSFETs exposed to ionizing radiation while operating in a 
          cryogenic environment. The transistors were exposed to low energy 
          x-rays while placed in a liquid nitrogen-cooled dewar Results 
          demonstrate significant performance and survivability advantages 
          for space-borne power MOSFETs operated at cryogenic temperatures. 
          The key advantages for low-temperature operation of power 
          MOSFET's in an ionizing radiation environment are: (1) steeper 
          subthreshold current slope before and after irradiation; (2) 
          lower off-state leakage currents before and after irradiation; 
          and (3) larger prerad threshold voltage for n-channel devices. 
          The first two points are also beneficial for devices that are not 
          irradiated, but the advantages are more significant in radiation 
          environments. The third point is only an advantage for commercial 
          devices operated in radiation environments. Results also 
          demonstrate that commercial off-the-shelf power MOSFETs can be 
          used for low-temperature operation in a limited total dose 
          environment (i.e., many space applications).
      KP: INTERFACE TRAPS, BORDER TRAPS, DEVICES, CENTERS, CHARGE, STATES

(46)  TI: STUDY OF PROTON RADIATION EFFECTS ON ANALOG IC DESIGNED FOR 
          HIGH-ENERGY PHYSICS IN A BICMOS-JFET RADHARD SOI TECHNOLOGY
      AU: BLANQUART_L, DELPIERRE_P, HABRARD_MC, MEKKAOUI_A, MOUTHUY_T, 
          DENTAN_M, DELAGNES_E, FOURCHES_N, ROUGER_M, TRUCHE_R, DELEVOYE_E, 
          DEPONTCHARRA_J, BLANC_JP, FLAMENT_O, LERAY_JL, MUSSEAU_O
      NA: CPPM,IN2P3,F-13288 MARSEILLE 9,FRANCE
          CENS,DSM,DAPNIA,F-91191 GIF SUR YVETTE,FRANCE
          CEA,DTA,LETI,F-38041 GRENOBLE,FRANCE
          CEN,CEA,F-91680 BRUYERES CHATEL,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2525-2529
      AB: We present experimental results from a fast charge amplifier and 
          a wideband analog buffer processed in the DMILL BiCMOS-JFET 
          radhard SOI technology and irradiated up to 4.5 x 10(14) 
          protons/cm(2). In parallel, we have irradiated elementary 
          transistors. These components were biased and electrical 
          measurements were done 30 min after beam stop. By evaluating 
          variations of main SPICE parameters, i. e., threshold voltage 
          shift for CMOS and current gain variation for bipolar 
          transistors, we have simulated the wideband analog buffer at 
          different doses. These SPICE simulations are in good agreement 
          with measured circuit degradations. The behavior of the charge 
          amplifier is consistent with extraction of transconductance and 
          pinch-off voltage shift of the PJFET.

(47)  TI: GAMMA-RAY AND FAST-NEUTRON RADIATION EFFECTS ON THIN-FILM 
          SUPERCONDUCTORS
      AU: COOKSEY_JW, BROWN_WD, ANG_SS, NASEEM_HA, ULRICH_RK, WEST_L
      NA: UNIV ARKANSAS,HIDEC,FAYETTEVILLE,AR,72701
          UNIV ARKANSAS,DEPT MECH ENGN,FAYETTEVILLE,AR,72701
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2521-2524
      AB: The gamma-ray and neutron radiation hardness of YBa2Cu3O7-x, 
          Tl2Ba2CaCu2O8+x, and Tl2Ba2Ca2Cu3O10+x superconducting thin films 
          deposited by off-axis sputtering and laser-ablation deposition 
          techniques on substrates of MgO and LaAlO3 was investigated. The 
          unbiased samples were irradiated with 662 keV gamma-rays up to a 
          cumulative dose of 1.5 Mrad(Si) and with neutron fluences up to 1 
          x 10(14) neutrons/cm(2).
          It was determined through nondestructive critical temperature 
          transition, T-c, and critical current density, J(c), measurements 
          and x-ray diffraction analysis that the thin film superconductors 
          were radiation hard up to moderate levels of neutrons and 
          gamma-rays. It was also determined that extended exposure to 
          moderately humid air degraded the critical current density of all 
          the films.
      KP: YBA2CU3O7-DELTA, IRRADIATION, TEMPERATURE

(48)  TI: MEASUREMENT OF CAPACITANCE TRANSIENTS WITH ATTOFARAD RESOLUTION 
          IN A MICROWAVE VARACTOR DIODE AFTER CO-60 IRRADIATION
      AU: SCARPULLA_J, YOUNG_AM, CHEN_J
      NA: AEROSP CORP,EL SEGUNDO,CA,90245
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2502-2510
      AB: A high resolution measurement system was constructed to 
          investigate transient capacitance changes in varactor diodes 
          after exposure to Co-60 photons. These capacitance transients, 
          while small, adversely affect the phase settling times of phase 
          lock loops used in spread spectrum communications systems. The 
          measurement system has a resolution of better than 10 aF, and 
          details are given concerning its design and operation. It was 
          used to study planar and mesa type Si varactor diodes. Small but 
          significant changes in the capacitive transients were observed 
          after irradiation. The behavior has been ascribed to the 
          generation of bulk defects caused by displacement damage in the 
          active layer of the diodes, although interface state generation 
          at the oxide interfaces has not been ruled out. The effect of the 
          changes in the diode transient responses on the settling time of 
          a typical phase lock loop frequency synthesizer has been modeled. 
          The introduction rate of the bulk traps has been estimated to be 
          1 x 10(-3) to 4 x 10(-3) cm(-1) rad(-1).
      KP: SEMICONDUCTORS

(49)  TI: TOTAL-DOSE HARDNESS OF FIELD-PROGRAMMABLE GATE ARRAYS
      AU: LUM_GK, MAY_RJ, ROBINETTE_LE
      NA: LOCKHEED MISSILES & SPACE CO INC,SUNNYVALE,CA,94088
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2487-2493
      AB: In this paper we present the effect of total dose ionization of 
          nonhardened field programmable gate arrays considered for space 
          applications. By irradiating test structures and modeling the 
          circuits that include total dose degradation, the basic leakage 
          mechanism in the design at elevated temperature can be 
          understood. Results show that a large array of CMOS inverter 
          structures will conduct large currents when the threshold 
          voltages of the p and n-channel transistors reach the transition 
          point of switching. Results show that if the n- and p-channel 
          thresholds were to be increased in the process, this problem can 
          be mitigated and hardness above 100 krad(Si) can be achieved.
      KP: DEVICES

(50)  TI: A MODEL FOR THE BIPOLAR-LIKE RESPONSE OF GAAS-MESFETS TO A 
          HIGH-DOSE-RATE ENVIRONMENT
      AU: ISLAM_NE, HOWARD_JW, FAGEEHA_O, BLOCK_RC, BECKER_M
      NA: RENSSELAER POLYTECH INST,DEPT NUCL ENGN & ENGN PHYS,TROY,NY
          OREGON GRAD INST,PORTLAND,OR
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2494-2501
      AB: A model for bipolar mechanism, initiated in some MESFETs during a 
          radiation transient is presented. It differs from other models in 
          ifs postulation that the 'neutral base' is formed during the 
          transient and is not present during normal device operation. The 
          response mechanism is due to the geometry of the device and does 
          not depend on its material properties.
      KP: INDUCED CHARGE COLLECTION

(51)  TI: A RADIATION-HARDENED 32-BIT MICROPROCESSOR-BASED ON THE 
          COMMERCIAL CMOS PROCESS
      AU: YOSHIOKA_S, KAMIMURA_H, AKIYAMA_M, NAKAMURA_M, TAMURA_T, 
          KUBOYAMA_S
      NA: HITACHI LTD,DIV SEMICOND & INTEGRATED CIRCUITS,TOKYO 187,JAPAN
          NATL SPACE DEV AGCY JAPAN,TOKYO 105,JAPAN
          HITACHI LTD,TOKYO 10110,JAPAN
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2481-2486
      AB: A radiation-hardened 32-bit microprocessor based on the 
          commercial CMOS process, usable up to 1 kGy(Si), has been 
          developed by (1) adding a silicon nitride passivation layer and 
          (2) thinning the field oxide. Both techniques suppress the 
          leakage current generated by the parasitic MOSFET, because its 
          negative threshold voltage shift due to oxide trapped holes is 
          decreased by the-latter, and compensated by the positive shift 
          due to the interface states generated during irradiation by 
          hydrogen napped in the oxide through the silicon-nitride 
          deposition. The samples supplied with 4.5 V and 20 MHz clock were 
          able to operate normally up to the total dose of 1.3 kGy(Si). The 
          total dose tolerance of the samples was over 20 times as much as 
          that of ones based on the commercial process.

(52)  TI: DEVELOPMENT OF A RADIATION-HARDENED NPN BIPOLAR-TRANSISTOR FOR A 
          64K CMOS FUSIBLE-LINK PROM
      AU: FULLER_R, NEWMAN_W
      NA: HARRIS SEMICOND INC,POB 883,MELBOURNE,FL,32902
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2474-2480
      AB: A 1.2 mu m CMOS production process was adapted to produce a 64K 
          CMOS fusible-link Programmable Read-Only Memory (FROM) for space 
          applications. The circuit requirement of less than 50 nS access 
          time combined with the need for 9 volt single pulse programming 
          of the fusible links and radiation tolerance to levels over 300 
          Krad(Si) made close collaboration between design engineering, 
          reliability engineering, and device engineering essential for a 
          successful project. A vertical NPN bipolar transistor was 
          integrated into a standard CMOS process to be used for 
          programming and reading the fuses. The device characteristics 
          were carefully matched to the product speed and programmability 
          requirements. The NPN device was optimized for radiation 
          performance. Successful development required extensive use of 
          process and device modeling, test structure design and 
          measurement, and experimental design methods.

(53)  TI: A NEW PROCEDURE FOR STATIC RAM EVALUATION UNDER X-RAY PULSES
      AU: MAREC_R, MARY_P, FERRANT_R, FAIRBANK_X, GAILLARD_R, PALAU_JM, 
          GASIOT_J
      NA: NUCLETUDES SA,AV HOGGAR,ZA COURTABOEUF ORSAY BP 117,F-91944 LES 
          ULIS,FRANCE
          LRBA,F-27207 VERNON,FRANCE
          THOMSON CSF,SEMICOND SPECIFIQUES,F-38521 ST EGREVE,FRANCE
          UNIV MONTPELLIER 2,CTR ELECTR MONTPELLIER,F-34095 MONTPELLIER 
          5,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2467-2473
      AB: An original method, to identify the initial patterns that are the 
          most favourable to obtain upsets under X-ray pulses, has been 
          developed on Static RAMs in the standby mode. The results 
          obtained with these initial patterns are interesting in order to 
          analyse the radiation induced failures.
      KP: UPSET

(54)  TI: TOTAL IONIZING DOSE EFFECTS ON HIGH-RESOLUTION (12-BIT, 14-BIT) 
          ANALOG-TO-DIGITAL CONVERTERS
      AU: LEE_CI, RAX_BG, JOHNSTON_AH
      NA: CALTECH,JET PROP LAB,4800 OAK GROVE DR,PASADENA,CA,91109
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2459-2466
      AB: This paper reports total dose radiation test results for high 
          resolution 12-/14-bit A/D converters. Small changes in internal 
          components can cause these devices to fail their specifications 
          at relatively low total dose levels. Degradation of 
          signal-to-noise ratio becomes increasingly important for 
          high-accuracy converters. Rebound effects in the thick-oxide MOS 
          devices cause these responses to be different at low and high 
          dose rates, which is a major concern for space applications.
      KP: A/D CONVERTERS

(55)  TI: RADIATION EFFECTS IN 5-VOLT AND ADVANCED LOWER VOLTAGE DRAMS
      AU: SHAW_DC, SWIFT_GM, PADGETT_DJ, JOHNSTON_AH
      NA: CALTECH,JET PROP LAB,4800 OAK GROVE DR,PASADENA,CA,91109
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2452-2458
      AB: This work examines the effects of ionizing radiation on highly 
          scaled DRAMs. Several 4 Mb and 16 Mb DRAMs with 5.0, 3.6, and 3.3 
          volt memory arrays are compared. A novel approach using memory 
          cell retention time is introduced and applied that allows insight 
          into the effects of radiation on individual devices within a DRAM 
          array. Data from this new application of retention time exhibits 
          significant changes due to ionizing radiation, even at low levels 
          where other device parameters do not change significantly. The 
          parameter, tau (50%), is introduced that helps classify DRAM 
          radiation response. Data are presented showing that there are two 
          different damage mechanisms that affect DRAM radiation response. 
          Finally, a relationship between threshold voltage and retention 
          time is shown for several DRAMs.
      KP: RANDOM-ACCESS MEMORIES, 16-MB CMOS SRAM, 256-MB DRAM, DEPENDENCE, 
          CIRCUITS, MODEL

(56)  TI: THE SURFACE GENERATION HUMP IN IRRADIATED POWER MOSFETS
      AU: ANDERSON_SR, ZUPAC_D, SCHRIMPF_RD, GALLOWAY_KF
      NA: UNIV ARIZONA,DEPT ELECT & COMP ENGN,TUCSON,AZ,85721
          INTEL CORP,CHANDLER,AZ,85226
          SEMATECH,AUSTIN,TX,78741
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2443-2451
      AB: A method of quantifying near midgap-level interface traps, 
          capture cross section, and changes in oxide-trapped charge using 
          a surface generation hump in the subthreshold curve (I-d vs. V-g) 
          of power MOSFETs is developed, The surface generation hump is a 
          result of the generation of carriers from traps at the depleted 
          Si-SiO2 interface in a gated diode-type structure. The charge 
          neutrality point of the hump is determined, and shifts of this 
          point are due solely to changes in oxide-trapped charge, Another 
          point is used to determine the stretchout of the hump, and thus 
          the interface trap density. With the interface trap density 
          determined, the capture cross section is extracted from the 
          surface generation velocity.
      KP: OXIDE-SEMICONDUCTOR DEVICES, INTERFACE STATE DENSITY, CHARGE, 
          TRAPS

(57)  TI: GERMANIUM CONTENT DEPENDENCE OF RADIATION-DAMAGE IN STRAINED 
          SI1-XGEX EPITAXIAL DEVICES
      AU: OHYAMA_H, VANHELLEMONT_J, TAKAMI_Y, HAYAMA_K, SUNAGA_H, 
          POORTMANS_J, CAYMAX_M, CLAUWS_P
      NA: KUMAMOTO NATL COLL TECHNOL,2659-2,SUYA,KUMAMOTO 86111,JAPAN
          IMEC,B-3001 LOUVAIN,BELGIUM
          RIKKYO UNIV,INST ATOM ENERGY,YOKOSUKA,KANAGAWA 24001,JAPAN
          JAPAN ATOM ENERGY RES INST,TAKASAKI RADIAT CHEM RES 
          ESTAB,TAKASAKI,GUMMA 37012,JAPAN
          RUG,B-9000 GHENT,BELGIUM
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2437-2442
      AB: The irradiation damage in n(+)-Si/p(+)-Si1-xGex epitaxial diodes 
          and n(+)-Si/p(+)-Si1-xGex/n-Si epitaxial heterojunction bipolar 
          transistors (HBTs) by fast neutrons and MeV electrons is studied 
          as a function of fluence and germanium content for the first 
          time. The degradation of the electrical performance of both 
          diodes and HBTs by irradiation increases with increasing fluence, 
          while it decreases with increasing germanium content. The damage 
          coefficient of reverse current for x = 0.12 and 0.16 diodes 
          irradiated by neutrons is calculated to be 6.2 x 10(-21) and 5.5 
          x 10(-21) n(-1)Acm(2), respectively. That of h(FE) for 
          electron-irradiated x = 0.08, 0.12 and 0.16 HBTs is 7.6 x 
          10(-16), 2.7 x 10(-16) and 1.6 x 10(-16) e(-1)cm(2), 
          respectively.
      KP: ELECTRON-IRRADIATION, SILICON, DEFECT

(58)  TI: STUDY OF PUNCH-THROUGH CHARACTERISTICS IN IRRADIATED MOSFETS
      AU: PACCAGNELLA_A, BISELLO_D, DAROLD_M, GOTRA_Y, BENETTI_P
      NA: UNIV CAGLIARI,IST ELETTRITECN,PIAZZA ARMI,I-09123 CAGLIARI,ITALY
          IST NAZL FIS NUCL,SEZ PADOVA,I-35131 PADUA,ITALY
          UNIV PADUA,DIPARTIMENTO FIS,I-35131 PADUA,ITALY
          UNIV PAVIA,DIPARTIMENTO CHIM GEN,I-27100 PAVIA,ITALY
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2511-2520
      AB: The DC and low frequency AC characteristics of the punch-through 
          (PT) conduction have been examined in MOSFETs with different 
          channel width/length ratios, fabricated on high resistivity Si 
          substrates. The experimental results can be fitted by an 
          analytical model deriving from a previous one developed for 
          BARRITT devices. The modifications on the PT conduction induced 
          by high dose neutron irradiation have been studied at various 
          temperatures. The effects due to the radiation induced deep 
          levels cannot be easily taken into account into the DC model, but 
          can still be interpreted by using the AC model of the device.
      KP: RESISTIVITY SILICON SUBSTRATE, SHORT-CHANNEL PMOSTS, DETECTORS, 
          MODEL

(59)  TI: TOTAL-DOSE EFFECTS IN CONVENTIONAL BIPOLAR-TRANSISTORS AND LINEAR 
          INTEGRATED-CIRCUITS
      AU: JOHNSTON_AH, SWIFT_GM, RAX_BG
      NA: CALTECH,JET PROP LAB,4800 OAK GROVE DR,PASADENA,CA
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2427-2436
      AB: Total dose damage is investigated for discrete bipolar 
          transistors and linear integrated circuits that are fabricated 
          with older processing technologies, but are frequently used in 
          space applications. The Kirk effect limits the current density of 
          discrete transistors with high collector breakdown voltage, 
          increasing their sensitivity to ionizing radiation because they 
          must operate low injection levels. Bias conditions during 
          irradiation had different effects on discrete and integrated 
          circuit transistors: discrete devices were strongly dependent on 
          bias conditions, whereas damage in the linear ICs was nearly the 
          same with or without bias. There were also large differences in 
          the response of these devices at low dose rates. None of the 
          discrete transistors exhibited enhanced damage at low dose rates, 
          whereas substantially more damage occurred in the linear devices 
          under low dose rate conditions, particularly for parameters that 
          rely directly on pnp transistors. The threshold for dose rate 
          effects in pnp transistors was about 0.01 rad(Si)/s, which is 
          approximately two orders of magnitude lower than the 
          corresponding threshold for npn transistors in integrated 
          circuits.
      KP: RADIATION, DEVICES

(60)  TI: SYNERGETIC EFFECTS OF RADIATION STRESS AND HOT-CARRIER STRESS ON 
          THE CURRENT GAIN OF NPN BIPOLAR JUNCTION TRANSISTORS
      AU: WITCZAK_SC, KOSIER_SL, SCHRIMPF_RD, GALLOWAY_KF
      NA: UNIV ARIZONA,DEPT ELECT & COMP ENGN,TUCSON,AZ,85721
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2412-2419
      AB: The combined effects of ionizing radiation and hot-carrier stress 
          on the current gain of npn bipolar junction transistors were 
          investigated. The analysis was carried out experimentally by 
          examining the consequences of interchanging the order in which 
          the two stress types were applied to identical transistors which 
          were stressed to various levels of damage. The results indicate 
          that the hot-carrier response of the transistor is improved by 
          radiation damage, whereas hot-carrier damage has little effect on 
          subsequent radiation stress. Characterization of the temporal 
          progression of hot-carrier effects revealed that hot-carrier 
          stress acts initially to reduce excess base current and improve 
          current gain in irradiated transistors. PISCES simulations show 
          that the magnitude of the peak electric-field within the 
          emitter-base depletion region is reduced significantly by net 
          positive oxide charges induced by radiation. The interaction of 
          the two stress types is explained in a qualitative model based on 
          the probability of hot-carrier injection determined by radiation 
          damage and on the neutralization and compensation of 
          radiation-induced positive oxide charges by injected electrons. 
          The results imply that a bound on damage due to the combined 
          stress types is achieved when hot-carrier stress precedes any 
          irradiation.
      KP: IONIZING-RADIATION, ELECTRON, DEGRADATION, GENERATION, MOSFETS, 
          DEFECTS, MODEL

(61)  TI: TOTAL-DOSE EFFECTS ON NEGATIVE VOLTAGE REGULATOR
      AU: BEAUCOUR_J, CARRIERE_T, GACH_A, LAXAGUE_D, POIROT_P
      NA: MATRA MARCONI SPACE,37 AVE LOUIS BREGNET BP1,F-78146 VELIZY 
          VILLACOUBL,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2420-2426
      AB: Functional failure at low dose level (4 Krad(Si)) on voltage 
          regulators (LM137) from different manufacturers are analysed. 
          Dose rate effects on parts hardness are evaluated, showing that 
          lowering the dose rate degrade more the IC's in the range 55 
          rad(Si)/s- 0,8 rad(Si)/s A failure mechanism is proposed, mainly 
          based on circuit analysis, voltage contrast measurements, local 
          irradiation and local electrical measurements with probe station. 
          A spice simulation was performed, providing quantitative 
          informations on the degradation. In the light of such a failure 
          analysis and dose rate effects, practical implications on 
          radiation assurance are discussed.

(62)  TI: CLEMENTINE RRELAX SRAM PARTICLE SPECTROMETER
      AU: BUEHLER_MG, SOLI_GA, BLAES_BR, RATLIFF_JM, GARRETT_HB
      NA: CALTECH,JET PROP LAB,4800 OAK GROVE DR,PASADENA,CA,91109
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2404-2411
      AB: The Clementine RRELAX radiation monitor chip consists of a p-FET 
          total dose monitor and a 4-kbit SRAM particle spectrometer. Eight 
          of these chips were included in the RRELAX and used to detect the 
          passage of the Clementine (S/C) and the innerstage adapter (ISA) 
          through the earth's radiation belts and the 21-Feb 1994 solar 
          flare. This is the first space flight for this 1.2-mu m rad-soft 
          custom CMOS radiation monitor. This paper emphasizes results from 
          the SRAM particle detector which showed that it (a) has a 
          detection range of five orders of magnitude relative to the 
          21-Feb solar flare; (b) is not affected by electrons, and (c) 
          detected microflares occurring with a 26.5-day period.
      KP: SOLAR

(63)  TI: ENVIRONMENTAL STABILITY OF LOW ABSORPTIVITY OPTICAL SOLAR 
          REFLECTORS AND THEIR IMPACT ON SPACECRAFT CHARGING
      AU: BOGORAD_A, HERSCHITZ_R, BOWMAN_C
      NA: MARTIN MARIETTA ASTRO SPACE,POB 800,PRINCETON,NJ,08543
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2400-2403
      AB: Charging properties and environmental stability of low 
          absorptivity ITO-coated optical solar reflectors (OSRs) were 
          tested. Ionizing radiation and UV had minimal impact. The use of 
          these OSRs will result in significant benefits to the thermal 
          subsystem without compromising spacecraft ESD control.
      KP: DISCHARGES

(64)  TI: EFFECTS OF REALISTIC SATELLITE SHIELDING ON SEE RATES
      AU: SMITH_EC
      NA: POB 880,MONTEAGLE,TN,37356
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2396-2399
      AB: Realistic models of satellite shielding have been used to 
          calculate SEE rates for Galactic Cosmic Rays (GCR) and solar 
          flare protons. The results are compared with those obtained with 
          a nominal 0.1 inch spherical shield. The rates for GCR (solar 
          minimum) are systematically lower than those calculated with the 
          nominal shield. The ratio of rates is greater than 75% for 
          lightly shielded devices, but may be as high as a factor of two 
          where there is shielding by other circuit boards. A more nearly 
          realistic estimate of the rates would be obtained with a 
          spherical shield with a thickness of at least 0.4 inches (3 
          gm/cm(2)) for the typical satellites considered.
          The calculation of the SEE rate due to protons was reformulated 
          to expedite shielding calculations. When the method was applied 
          to the 93L422 RAM for various flare spectra, it was apparent that 
          shielding has a first order effect on rate predictions. The 
          calculated flare upset rates for the TDRS satellite were within 
          20% of the observed rates. A spherical shield of thickness 0.3 
          inches (2 gm/cm(2)) would reproduce the rates. The method was 
          also applied to a trapped proton environment predicted from 
          standard models for CRRES. The predicted rate was consistent with 
          the uncertainties of the environment.
      KP: EVENT UPSET RATE, MODEL

(65)  TI: A SIMPLE ALGORITHM FOR PREDICTING PROTON SEU RATES IN-SPACE 
          COMPARED TO THE RATES MEASURED ON THE CRRES SATELLITE
      AU: REED_RA, MCNULTY_PJ, BEAUVAIS_WJ, ABDELKADER_WG, 
          STASSINOPOULOS_EG, BARTH_JCL
      NA: CLEMSON UNIV,DEPT PHYS & ASTRON,CLEMSON,SC,29634
          NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD,20771
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2389-2395
      AB: A new simulation code, the Clemson Onmidirectional Spallation 
          Model for Interaction in Circuits (COSMIC), is described and its 
          predictions agree with SEU data from four devices flown as part 
          of the microelectronics package experiment on the CRRES 
          satellite. The code uses CUPID for determining the energy 
          depositions in the sensitive volumes; it allows proton exposures 
          with arbitrary angles of incidence including random 
          omnidirectional exposure; and the user specifies the thickness of 
          shielding on six sides of the sensitive volume. COSMlC is used as 
          part of an algorithm developed to predict the rate proton induced 
          single event upsets occur in the space radiation environment 
          given by AP-8. In testing the algorithm, the position coordinates 
          are taken from the satellite's ephemeris data, but calculations 
          based on position coordinates from orbital codes were also in 
          agreement with the measured values.

(66)  TI: SINGLE EVENT UPSETS CORRELATED WITH ENVIRONMENT
      AU: VAMPOLA_AL, LAURIENTE_M, WILKINSON_DC, ALLEN_J, ALBIN_F
      NA: UNIV GREENBELT,RES FDN,6411 IVY LANE,GREENBELT,MD,20770
          NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD,20771
          NATL GEOPHYS DATA CTR,BOULDER,CO,80303
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2383-2388
      AB: Single Event Upset rates on satellites in different Earth orbits 
          are correlated with solar protons and geomagnetic activity and 
          also with the NASA AP8 proton model to extract information about 
          satellite anomalies caused by the space environment. An extensive 
          discussion of the SEU data base from the TOMS solid state 
          recorder and an algorithm for correcting spontaneous upsets in it 
          are included as an Appendix, SAMPEX and TOMS, which have the same 
          memory chips, have similar normalized responses in the South 
          Atlantic Anomaly, SEU rates due to solar protons over the polar 
          caps are within expectations. No geomagnetic activity effects can 
          be discerned in the SEU rates.

(67)  TI: RADIATION-BELT AND TRANSIENT SOLAR-MAGNETOSPHERIC EFFECTS ON 
          HIPPARCOS RADIATION BACKGROUND
      AU: DALY_EJ, VANLEEUWEN_F, EVANS_HDR, PERRYMAN_MAC
      NA: EUROPEAN SPACE AGCY,ESTEC,2200 AG NOORDWIJK,NETHERLANDS
          ROYAL GREENWICH OBSERV,CAMBRIDGE CB3 0EZ,ENGLAND
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2376-2382
      AB: The Hipparcos astrometry satellite operated in a 
          near-geostationary transfer orbit between august 1989 and August 
          1993. Its telescopes were sensitive to background signals induced 
          by energetic electrons and protons, and by bremsstrahlung. The 
          observations yielded a long-term data-set which strongly reflects 
          the structure of the radiation belts, their dynamics and the 
          effects of solar particle events. Investigation of these data 
          includes qualitative comparisons with GOES and CRRES data.
      KP: SATELLITE, CRRES

(68)  TI: APPLYING NEW SOLAR PARTICLE EVENT MODELS TO INTERPLANETARY 
          SATELLITE PROGRAMS
      AU: MCKERRACHER_PL, KINNISON_JD, MAURER_RH
      NA: JOHNS HOPKINS UNIV,APPL PHYS LAB,JOHNS HOPKINS RD,LAUREL,MD,20723
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2368-2375
      AB: Variability in the models and methods used for single event upset 
          (SEU) calculations in microelectronic memory devices can lead to 
          a range of possible upset rates. In order to compare the Adams 
          1986 interplanetary solar flare model to a new model proposed by 
          scientists at the Jet Propulsion Laboratory (JPL92) we have 
          calculated an array of upset rates using heavy ion and proton 
          data for selected DRAM and SRAM memories and for Actel Field 
          Programmable Gate Arrays (FPGAs). To make more general 
          comparisons of the models we have produced a set of engineering 
          curves of predicted upset rates versus hypothetical device 
          cross-section parameters. The results show that use of this more 
          realistic, although still conservative, JPL model can have 
          significant benefits for satellite programs, especially those 
          which must operate continuously during solar particle events. The 
          benefits include more flexibility in model choice, a higher level 
          of confidence in the environment, and potential cost savings by 
          the calculation of less pessimistic SEU rates which allow 
          designers to integrate commercial products into their spacecraft 
          design with the use of Error Detection and Correction (EDAC) 
          schemes.
      KP: GEOSYNCHRONOUS ORBIT, ABUNDANCES, FLARES, RATES

(69)  TI: THE SINGLE EVENT UPSET ENVIRONMENT FOR AVIONICS AT HIGH-LATITUDE
      AU: SIMS_AJ, DYER_CS, PEERLESS_CL, JOHANSSON_K, PETTERSSON_H, 
          FARREN_J
      NA: DEF RES AGCY,DEPT SPACE & COMMUN,FARNBOROUGH,HANTS,ENGLAND
          SAAB SCANIA AB,SAAB MIL AIRCRAFT,LINKOPING,SWEDEN
          AEA TECHNOL,HARWELL LAB,HARWELL INSTRUMENTS,HARWELL,OXON,ENGLAND
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2361-2367
      AB: Measurements of the high latitude SEU environment at avionics 
          altitude have been made on board a commercial airliner. Results 
          are compared with models of primary and secondary cosmic rays and 
          atmospheric neutrons. Ground based SEU tests of static RAMs are 
          used to predict rates in flight.
      KP: UPPER-ATMOSPHERE

(70)  TI: RADIATION ENVIRONMENT MEASUREMENTS WITH THE COSMIC-RAY 
          EXPERIMENTS ON-BOARD THE KITSAT-1 AND POSAT-1 MICRO-SATELLITES
      AU: UNDERWOOD_CI, BROCK_DJ, WILLIAMS_PS, KIM_S, DILAO_R, SANTOS_PR, 
          BRITO_MC, DYER_CS, SIMS_AJ
      NA: UNIV SURREY,CTR SATELLITE ENGN RES,GUILDFORD GU2 
          5XH,SURREY,ENGLAND
          KOREA ADV INST SCI & TECHNOL,SATELLITE TECHNOL RES CTR,TAEJON 
          305701,SOUTH KOREA
          INST SUPER TECN,DEPT FIS,P-1096 LISBON,PORTUGAL
          DRA,DEPT SPACE & COMMUN,FARNBOROUGH,HANTS,ENGLAND
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2353-2360
      AB: The success of the Cosmic Radiation Environment and Dosimetry 
          (CREDO) experiment carried on-board the UoSAT-3 micro-satellite 
          (launched in 1990) has lead to the development of a new: 
          instrument called the Cosmic-Ray Experiment (CRE) which has flown 
          on-board the KITSAT-1 and PoSAT-1 micro-satellites, launched in 
          1992 and 1993 respectively.
          The results from both CRE instruments show excellent agreement 
          with those of CREDO for the galactic cosmic-ray environment. 
          However, there are some differences in the CRE and CREDO response 
          to the trapped proton environment of the South Atlantic Anomaly 
          which can be explained by the differences in the detector 
          response time.
          The fit between the flight results and predictions from the 
          standard models is generally good, but some differences are 
          noted.
          The CRE and CREDO instruments should provide continuous coverage 
          of the near-Earth radiation environment across a complete solar 
          cycle. This is important in view of the dynamic nature of the 
          radiation environment - as amply demonstrated by the results from 
          the CRRES spacecraft [1].

(71)  TI: SEE IN-FLIGHT MEASUREMENT AN THE MIR ORBITAL STATION
      AU: FALGUERE_D, DUZELLIER_S, ECOFFET_R
      NA: CERT,ONERA,DEPT ETUD & RECH TECHNOL SPATIALE,2 AVE EDOUARD 
          BELIN,F-31055 TOULOUSE,FRANCE
          CTR NATL ETUD SPATIALES,DEPT COMPOSANTS ELECTR,F-31055 
          TOULOUSE,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2346-2352
      AB: SEE spaceflight measurements are presented on HM65756 SRAM from 
          Matra-MHS, Seeq 28C256 and Motorola MC68020 microprocessor (bulk 
          version) in the MIR station orbit (350 km altitude, 51.6 degrees 
          inclination). Accelerator testing (heavy ion and proton) of 
          flight spares permits the prediction of the event rates using 
          standard model such as CREME and SPACERAD(1) as well as 
          characterisations of the flight components allowing the 
          comparison of in-orbit observations. Event rate prediction and 
          ground-testing data are compared.

(72)  TI: BIOPAN - FLIGHT EXPERIMENT CARD
      AU: HARBOESORENSEN_R, MEIJER_H, RONNET_JC, DEMETS_R, ADAMS_L, 
          HEINRICH_W, ROCHER_H
      NA: EUROPEAN SPACE AGCY,ESTEC,2200 AG NOORDWIJK,NETHERLANDS
          UNIV GESAMTHSCH SIEGEN,DEPT PHYS,W-5900 SIEGEN,GERMANY
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2340-2345
      AB: As part of the BIOPAN-0 test flight payload, ESA/ESTEC together 
          with University of Siegen, designed an experiment called CARD, 
          for flight on the first BIOPAN model. The CARD experiment, 
          consisting of commercially available 128K-bit EEPROM cards and 
          CR-39 plastic nuclear track detector foils, was flown in order to 
          assess the EEPROMs sensitivity to cosmic rays and the CR-39 foils 
          to measure the cosmic rays seen during the mission. The EEPROMs 
          were unbiased during the flight so only the charged content of 
          the memories could be assessed after returning to earth.
          This paper presents the results from a 15.6 day flight on-board 
          the Russian Photon-8 satellite, launched October the 8th 1992 
          (altitude 300 km, inclination 62.8 degrees), and gives details of 
          the ground testing and analyses performed.

(73)  TI: MEASUREMENT AND MODELING OF RADIATION RESPONSE OF MULTILAYER 
          BESOI BURIED INSULATORS
      AU: BOESCH_HE, PENNISE_CA
      NA: USA,RES LAB,2800 POWDER MILL RD,ADELPHI,MD,20783
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2322-2331
      AB: The time- and temperature-dependent radiation responses of 
          multilayer bond-and-etch buried insulators were measured with the 
          use of a fast capacitance-voltage technique after short-pulse 
          irradiation. The multilayer insulators were fabricated with 
          various combinations of SiO2, silicon nitride, nitrided SiO2, and 
          reoxidized nitrided SiO2 layers. The charge response results were 
          analyzed together with x-ray-induced photocurrent results with 
          simple charge-buildup models to determine the charge trapping 
          characteristics of the complex structures. To a first 
          approximation, these responses were predictable from the known 
          general trapping characteristics of the component layers; 
          however, the detailed results showed substantial charge-trapping 
          variations with processing and indicated that bonding or 
          fabricating one insulator material on another can alter the 
          characteristics of either. Charge trapping in the bulk and at the 
          interfaces of the SiO2 layers was particularly sensitive to these 
          process variations.
      KP: SILICON-ON-INSULATOR, OXIDES, TRANSPORT, HOLE

(74)  TI: RADIATION RESPONSE OF FULLY-DEPLETED MOS-TRANSISTORS FABRICATED 
          IN SIMOX
      AU: JENKINS_WC, LIU_ST
      NA: USN,RES LAB,CODE 6816,WASHINGTON,DC,20375
          HONEYWELL SOLID STATE ELECTR CTR,PLYMOUTH,MN,55441
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2317-2321
      AB: The total dose radiation response of radiation-resistant 
          fully-depleted submicron n-MOS and p-MOS transistors fabricated 
          in SIMOX is presented. The total ionizing dose radiation induced 
          threshold voltage shifts under three different irradiation bias 
          conditions, including the worst case (pass-gate) bias for n-MOS 
          transistors are discussed. Total dose hard fully-depleted p-MOS 
          transistors are experimentally demonstrated. The larger threshold 
          voltage shifts of fully-depleted n-MOS transistors as compared to 
          partially-depleted n-MOS transistors in an ionizing radiation 
          environment are explained by a model coupling the radiation 
          induced buried oxide charge to the top transistor.
      KP: MOSFETS

(75)  TI: NOISE CHARACTERIZATION OF TRANSISTORS IN A 1.2-MU-M CMOS SOI 
          TECHNOLOGY UP TO A TOTAL-DOSE OF 12-MRAD-(SI)
      AU: FACCIO_F, BIANCHI_M, FORNASARI_M, HEIJNE_EHM, JARRON_P, ROSSI_G, 
          BOREL_G, REDOLFI_J
      NA: CERN,CH-1211 GENEVA 23,SWITZERLAND
          THOMSON TCS,ST EGREVE,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2310-2316
      AB: The analog performance of the Thomson HSOI3-HD technology has 
          been measured up to a total dose of 12 Mrad(Si) of ionizing 
          radiation (Co-60). The threshold voltage shift is -170 mV for 
          p-channel and -20 mV for n-channel transistors. Transconductance 
          degradation is respectively 4% and 17%. Noise has been measured 
          in the 500 Hz-25 MHz bandwidth. In addition to the I/f and white 
          noise, a generation-recombination contribution appears in the 
          noise spectrum. This contribution is sensitive to the bias 
          applied to the backgate and body electrodes. The white noise 
          increase after irradiation is 16% for p-channel and 35% for 
          n-channel transistors. p-channel transistors have very low I/f 
          noise and are less sensitive to irradiation effects.
      KP: SIMOX

(76)  TI: FULLY-DEPLETED SUBMICRON SOI FOR RADIATION-HARDENED APPLICATIONS
      AU: BRADY_FT, SCOTT_T, BROWN_R, DAMATO_J, HADDAD_NF
      NA: LORAL FED SYST,9500 GODWIN DR,MANASSAS,VA,22110
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2304-2309
      AB: Using fully-depleted technology, the Loral 256K SOI SRAM has 
          demonstrated under worst case SEU and prompt dose testing an LET 
          threshold of at least 80 MeV*cm ($) over cap 2/mg, and a prompt 
          dose rate upset level of greater then 4E10 rad(Si)/s, 
          respectively, without design hardening. Total dose testing on 
          transistors fabricated on enhanced bond and etchback SOI 
          substrates indicates over 100 krad(Si) capability. Together, 
          these results represent the first description of a fully depleted 
          SOI technology for all radiation-hardened applications except 
          extreme total dose.

(77)  TI: THEORETICAL-STUDY OF SEUS IN 0.25-MU-M FULLY-DEPLETED CMOS SOI 
          TECHNOLOGY
      AU: BRISSET_C, DOLLFUS_P, MUSSEAU_O, LERAY_JL, HESTO_P
      NA: UNIV PARIS 11,INST ELECTR FONDAMENTALE,CNRS,URA 22,F-91405 
          ORSAY,FRANCE
          CEA,SERV ELECTR,F-91680 BRUYERES CHATEL,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2297-2303
      AB: We present a theoretical study of die behavior of basic CMOS/SOI 
          inverter and static memory; cell struck by an energetic ion. This 
          work is based oil 3D Monte Carlo device simulation. CMOS cells 
          are made up of ultra-thin SOI film 0.25 mu m MOSFETs without body 
          ties operating in fully-depleted mode. The ion track is simulated 
          by electron-hole pairs generation with an energy of 1 eV for each 
          carrier. We took a particular care to quantify the radiation 
          effect as a function of Linear Energy Transfer (LET) of the ion. 
          After irradiation of the off-state N-MOS of the inverter, 
          electrons in excess are drained-off by source and drain contacts. 
          Due to the lack of hole contact, excess holes tend to remain 
          accumulated in the channel initiating a parasitic bipolar 
          transistor mechanism. The electron current, flowing from source 
          to drain, discharges the output capacitor, which result in a 
          transient upset. The recovery time is then controlled by 
          recombination of excess holes. For memory cell, even after 
          recombination of excess holes stored in the channel, the return 
          to initial logic state could not be achieved, which constitutes a 
          definitive single event upset (SEU). As this would occur for LET 
          as low as 3 MeV.cm(2).mg(-1), hardening techniques for 0.25 mu m 
          CMOS/SOI devices are finaly discussed.
      KP: MONTE-CARLO, SILICON, TRANSPORT, CIRCUITS

(78)  TI: IMPROVEMENT OF RADIATION HARDNESS IN FULLY-DEPLETED SOI N-MOSFETS 
          USING GE-IMPLANTATION
      AU: WEI_HF, CHUNG_JE, KALKHORAN_NM, NAMAVAR_F, ANNAMALAI_NK, SHEDD_WM
      NA: SHARP MICROELECTR TECHNOL INC,5700 NW PACIFIC RIM 
          BLVD,CAMAS,WA,98607
          MIT,DEPT ELECT ENGN & COMP SCI,CAMBRIDGE,MA,02139
          SPIRE CORP,BEDFORD,MA,01730
          PHILLIPS LAB,VTER,BEDFORD,MA,01731
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2291-2296
      AB: This work demonstrates a well-controlled technique of channel 
          defect engineering by implanting germanium into the channel of a 
          Silicon-On-insulator (SOI) MOSFET to generate subgap energy 
          states. These subgap states act as minority-carrier lifetime 
          killers to reduce parasitic bipolar effects. The Ge-implant also 
          serves the dual purpose of positioning most of the subgap states 
          in the back interface region which retard the total dose 
          responses of off-state leakage and front-channel threshold 
          voltage.
      PA: 5186785 US;ANNAMALAI_NK{1993}
      KP: TRANSISTORS

(79)  TI: EFFECT OF SUPPLEMENTAL O-IMPLANTATION ON THE RADIATION-INDUCED 
          HOLE TRAPS IN SIMOX BURIED OXIDES
      AU: ZVANUT_ME, BENEFIELD_C, HUGHES_HL
      NA: UNIV ALABAMA,BIRMINGHAM,AL,35294
          USN,RES LAB,WASHINGTON,DC,20375
          ARACOR,WASHINGTON,DC
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2284-2290
      AB: We describe electrical and spectroscopic measurements of SIMOX 
          subjected to supplemental oxygen implantation and standard 1000 
          degrees C post implantation annealing. Point contact transistor 
          measurements indicate that the supplemental oxygen implantation 
          creates a net increase in radiation-induced trapped charge, and, 
          surprisingly, electron paramagnetic resonance studies show that 
          the O vacancy concentration increases. The electron paramagnetic 
          resonance results suggest that the radiation tolerance of the 
          supplemental oxides is due to insufficiently annealed 
          implantation damage. A higher post supplemental anneal 
          temperature minimizes the radiation-induced trapped charge; but 
          further studies are necessary to assess the total impact of the 
          high temperature anneal.
      KP: ELECTRON, SILICON, SIO2, CENTERS, CHARGE, OXYGEN

(80)  TI: THE USE OF SPECTROSCOPIC ELLIPSOMETRY TO PREDICT THE RADIATION 
          RESPONSE OF SIMOX
      AU: MRSTIK_BJ, MCMARR_PJ, LAWRENCE_RK, HUGHES_HL
      NA: USN,RES LAB,CODE 6816,WASHINGTON,DC,20375
          SFA INC,LANDOVER,MD,20785
          SFA,ARACOR,WASHINGTON,DC,20375
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2277-2283
      AB: We have studied SIMOX (Separation by Implantation of Oxygen) 
          material using spectroscopic ellipsometry to determine the 
          structure of the buried oxide and C-V measurements to determine 
          the radiation response of the buried oxide. Our ellipsometric 
          measurements indicate that the buried oxide is best described as 
          a layer of stoichiometric SiO2 which is more dense than bulk 
          vitreous (v-) SiO2. We also find that the radiation response of 
          the buried oxide is determined primarily by its density. We also 
          find that small variations in the conditions used to prepare the 
          SIMOX wafer can significantly affect the oxide density and its 
          radiation response. The density of the buried oxide is also found 
          to affect how it etches.
      KP: BURIED OXIDES

(81)  TI: PROTON IRRADIATION EFFECTS ON ADVANCED DIGITAL AND MICROWAVE 
          III-V COMPONENTS
      AU: HASH_GL, SCHWANK_JR, SHANEYFELT_MR, SANDOVAL_CE, CONNORS_MP, 
          SHERIDAN_TJ, SEXTON_FW, SLAYTON_EM, HEISE_JA, FOSTER_CC
      NA: SANDIA NATL LABS,ALBUQUERQUE,NM,87185
          INDIANA UNIV,CYCLOTRON FACIL,BLOOMINGTON,IN
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2259-2266
      AB: A wide range of advanced III-V components suitable for use in 
          high-speed satellite communication systems were evaluated for 
          displacement damage and single-event effects in high-energy, 
          high-fluence proton environments. Transistors and integrated 
          circuits (both digital and MMIC) were irradiated with protons at 
          energies from 41 to 197 MeV and at fluences from 10(10) to 
          2x10(14) protons/cm(2). Large soft-error rate were measured for 
          digital GaAs MESFET (3x10(-5) errors/bit-day) and heterojunction 
          bipolar circuits (10(-5) errors/bit-day). No transient signals 
          were detected from MMIC circuits. The largest degradation in 
          transistor response caused by displacement damage was observed 
          for 1.0-mu m depletion- and enhancement-mode MESFET transistors. 
          Shorter gate length MESFET transistors and HEMT transistors 
          exhibited less displacement-induced damage. These results show 
          that memory-intensive GaAs digital circuits may result in 
          significant system degradation due to single-event upset in 
          natural and man-made space environments. However, displacement 
          damage effects should not be a limiting factor for fluence levels 
          up to 10(14) protons/cm(2) [equivalent to total doses in excess 
          of 10 Mrad(GaAs)].
      KP: RADIATION HARDNESS, GAAS, UPSETS

(82)  TI: SINGLE EVENT UPSET AT GIGAHERTZ FREQUENCIES
      AU: SHOGA_M, JOBE_K, GLASGOW_M, BUSTAMANTE_M, SMITH_E, KOGA_R
      NA: HUGHES SPACE & COMMUN,LOS ANGELES,CA,90009
          AEROSP CORP,EL SEGUNDO,CA,90245
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2252-2258
      AB: Single Event Upset (SEU) characteristics of a digital emitter 
          coupled logic (ECL) device clocking at 0:5, 1, and 3.2 GHz and at 
          temperatures of 5, 75, and 105 degrees C are presented. The test 
          technique is explained. Observations of two types of upsets, 
          phase upsets at low Linear Energy Transfer (LETs) and amplitude 
          upsets at high LETs are also presented. The cause of phase upsets 
          is discussed: The effect of each type of upset on the system is 
          discussed. The upset cross section and LET threshold seem to be 
          insensitive to temperatures below 75 degrees C and to the clock 
          frequencies tested.

(83)  TI: SINGLE EVENT UPSETS IN GALLIUM-ARSENIDE DYNAMIC LOGIC
      AU: FOUTS_DJ, WEATHERFORD_T, MCMORROW_D, MELINGER_JS, CAMPBELL_AB
      NA: USN,POSTGRAD SCH,DEPT ECE,MONTEREY,CA
          SFA INC,LANDOVER,MD,20785
          USN,RES LAB,WASHINGTON,DC,20375
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2244-2251
      AB: The advantages and disadvantages of using gallium arsenide (GaAs) 
          dynamic logic in computers and digital systems are briefly 
          discussed, especially with respect to space applications. A short 
          introduction to the topology and operation of GaAs Two-Phase 
          Dynamic FET Logic (TDFL) circuits is presented. Experiments for 
          testing the SEU sensitivity of GaAs TDFL, using a laser to create 
          charge collection events, are described. Results are used to 
          estimate the heavy-ion, soft error rate for TDFL in a spacecraft 
          in geosynchronous orbit, and the dependence of the SEU 
          sensitivity on clock frequency, clock voltage, and clock phase. 
          Analysis of the data includes a comparison between the SEU 
          sensitivities of TDFL and the more common static form of GaAs 
          logic, Directly Coupled FET Logic (DCFL). This is the first 
          reported SEU testing of GaAs dynamic logic.
      KP: CHARGE-COLLECTION, GAAS-MESFETS

(84)  TI: SOI68T020 HEAVY-IONS EVALUATION
      AU: LESTRAT_P, TERRIER_C, ESTREME_F, ROSIER_LH
      NA: THOMSON CSF,SEMICOND SPECIF,AVE ROCHEPLEINE,BP 123,F-38521 ST 
          EGREVE,FRANCE
          CTR NATL ETUD SPATIALES,F-31055 TOULOUSE,FRANCE
          INST PHYS NUCL LYON,FAC SCI,F-91406 ORSAY,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2240-2243
      AB: THOMSON-CSF Semiconducteurs Specifiques (TCS) and the CEA-LETI 
          have developed a 0.8 mu m SOI bulk compatible process (HSOI4CB) 
          for space and battle field applications. The main motivation for 
          this process is to allow the transfer of already existing bulk 
          circuits onto SOI with reduced redesign effort and performances 
          degradation. In this paper, SOI process (HSOI4CB) and the 68020 
          transfer are summarized, including the most significant 
          characteristics of the resulting product (68T020), in terms of 
          Single Event Upset (SEU) and Single Event Latch-up (SEL). For the 
          same revision version, the 68T020 comparisons with bulk or 
          epitaxial 68020 processes are given.

(85)  TI: CHARACTERIZATION OF SINGLE HARD ERRORS (SHE) IN 1M-BIT SRAMS FROM 
          SINGLE-ION
      AU: POIVEY_C, CARRIERE_T, BEAUCOUR_J, OLDHAM_TR
      NA: MATRA MARCONI SPACE,37 AVE LOUIS BREGUET,BP1,F-78146 VELIZY 
          VILLACOUBL,FRANCE
          USA,RES LAB,ADELPHI,MD,20783
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2235-2239
      AB: A Single Hard Error (SHE) characterization was performed on two 
          types of 1Mbit SRAMs : MT5C1008 from MICRON and MSM8128 from 
          HITACHI. On both types, test results showed that one single ion 
          is sufficient to create a stuck bit. On orbit SHE rate 
          calculation showed that the probability to have a stuck bit in 
          space on a single 1Meg SRAM is rather low.
      KP: HEAVY

(86)  TI: 2 CMOS MEMORY CELLS SUITABLE FOR THE DESIGN OF SEU-TOLERANT VLSI 
          CIRCUITS
      AU: VELAZCO_R, BESSOT_D, DUZELLIER_S, ECOFFET_R, KOGA_R
      NA: IMAG LAB GRENOBLE,GENIE INFORMAT LAB,46 AV FELIX VIALLET,F-38031 
          GRENOBLE,FRANCE
          DERTS,ONERA,CERT,F-31055 TOULOUSE,FRANCE
          CTR NATL ETUD SPATIALES,F-31055 TOULOUSE,FRANCE
          AEROSP CORP,LOS ANGELES,CA,90009
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2229-2234
      AB: Two new CMOS memory cells, called HIT cells, designed to be 
          SEU-immune are presented. Compared to previously reported design 
          hardened solutions, the HIT cells feature better electrical 
          performances and consume less silicon area. SEU tests performed 
          on a prototype chip prove the efficiency of the approach.

(87)  TI: THE EFFECT OF LAYOUT MODIFICATION ON LATCHUP TRIGGERING IN CMOS 
          BY EXPERIMENTAL AND SIMULATION APPROACHES
      AU: DELAROCHETTE_H, BRUGUIER_G, PALAU_JM, GASIOT_J, ECOFFET_R
      NA: UNIV MONTPELLIER 2,CTR ELECTR,F-34095 MONTPELLIER 05,FRANCE
          CTR NATL ETUD SPATIALES,F-31055 TOULOUSE,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2222-2228
      AB: The influence of certain geometrical parameters on latchup 
          triggering in CMOS-1.2 mu m structure is studied by means of 
          experiments and simulations on test structures. Electrical 
          characterizations are made in order to validate quantitatively 
          the analysis achieved by numerical simulations. The results of 
          heavy ion irradiation from two different sources are given and 
          discussed with regard to the influence of the same geometrical 
          parameters on the sensitivity of the test structures to latchup.
      KP: HOLDING VOLTAGE

(88)  TI: TEMPERATURE AND ANGULAR-DEPENDENCE OF SUBSTRATE RESPONSE IN SEGR
      AU: MOURET_I, ALLENSPACH_M, SCHRIMPF_RD, BREWS_JR, GALLOWAY_KF, 
          CALVEL_P
      NA: UNIV ARIZONA,DEPT ELECT & COMP ENGN,TUCSON,AZ,85721
          ALCATEL ESPACE,TOULOUSE,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2216-2221
      AB: This work examines the role of the substrate response in 
          determining the temperature and angular dependence of 
          Single-Event Gate Rupture (SEGR). Experimental data indicate that 
          the likelihood of SEGR increases when the temperature of the 
          device is increased or when the incident angle is made closer to 
          normal. In this work, simulations are used to explore this 
          influence of high temperature on SEGR and to support physical 
          explanations for this effect. The reduced hole mobility at high 
          temperature causes the hole concentration at the oxide-silicon 
          interface to be greater, increasing the transient oxide field 
          near the strike position. In addition, numerical calculations 
          show that the transient oxide field decreases as the ion's angle 
          of incidence is changed from normal. This decreased field 
          suggests a lowered likelihood for SEGR, in agreement with the 
          experimental trend.

(89)  TI: SINGLE EVENT BURNOUT OF POWER MOSFETS CAUSED BY NUCLEAR-REACTIONS 
          WITH HEAVY-IONS
      AU: KUBOYAMA_S, MATSUDA_S, KANNO_T, HIROSE_T
      NA: NATL SPACE DEV AGCY JAPAN,TSUKUBA SPACE CTR,2-1-1 
          SENGEN,TSUKUBA,IBARAKI 305,JAPAN
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2210-2215
      AB: Single event burnout (SEB) phenomenon of power MOSFETs caused by 
          nuclear reactions with incident heavy ions has been probed 
          experimentally. 520MeV Kr and 3536MeV Xe ions having the same LET 
          were used as incident ions for the experiment. The observed SEB 
          threshold voltage was quite different for both ions. Detailed 
          analysis revealed that the Xe ions can produce excess charge as a 
          result of nuclear reactions with Si atoms. The result suggests 
          that usual SEB immunity test as a function of LET is not adequate 
          for high voltage devices that have much larger sensitive volume.

(90)  TI: SINGLE EVENT UPSET AND CHARGE COLLECTION MEASUREMENTS USING 
          HIGH-ENERGY PROTONS AND NEUTRONS
      AU: NORMAND_E, OBERG_DL, WERT_JL, NESS_JD, MAJEWSKI_PP, WENDER_S, 
          GAVRON_A
      NA: BOEING DEF & SPACE GRP,SEATTLE,WA,98124
          LOS ALAMOS NATL LAB,LOS ALAMOS,NM,87545
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2203-2209
      AB: RAMs, microcontrollers and surface barrier detectors were exposed 
          to beams of high energy protons and neutrons to measure the 
          induced number of upsets as well as energy deposition. The WNR 
          facility at Los Alamos provided a neutron spectrum similar to 
          that of the atmospheric neutrons. Its effect on devices was 
          compared to that of protons with energies of 200, 400, 500 and 
          800 MeV. Measurements indicate that SEU cross sections for 400 
          MeV protons are similar to those induced by the atmospheric 
          neutron spectrum.
      KP: UPPER-ATMOSPHERE, ENVIRONMENT

(91)  TI: IMPLICATIONS OF THE SPATIAL DEPENDENCE OF THE SINGLE-EVENT-UPSET 
          THRESHOLD IN SRAMS MEASURED WITH A PULSED-LASER
      AU: BUCHNER_S, LANGWORTHY_JB, STAPOR_WJ, CAMPBELL_AB, RIVET_S
      NA: SFA INC,LANDOVER,MD,20785
          USN,RES LAB,WASHINGTON,DC,20375
          HARRIS SEMICOND INC,SCHAUMBURG,IL,60173
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2195-2202
      AB: Pulsed laser light was used to measure single event upset (SEU) 
          thresholds for a large number of memory cells in both CMOS and 
          bipolar SRAMs. Results showed that small variations in intercell 
          upset threshold could not explain the gradual rise in the curve 
          of cross section versus linear energy transfer (LET). The memory 
          cells exhibited greater intracell variations implying that the 
          charge collection efficiency within a memory cell varies 
          spatially and contributes substantially to the shape of the curve 
          of cross section versus LET. The results also suggest that the 
          pulsed laser can be used for hardness-assurance measurements on 
          devices with sensitive areas larger than the diameter of the 
          laser beam.
      KP: SEU

(92)  TI: SINGLE EVENT EFFECTS IN ANALOG-TO-DIGITAL CONVERTERS - DEVICE 
          PERFORMANCE AND SYSTEM IMPACT
      AU: TURFLINGER_TL, DAVEY_MV, MAPPES_BM
      NA: USN,CTR SURFACE WARFARE,CRANE,IN,47522
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2187-2194
      AB: Monolithic Analog-to-Digital Converters (ADCs) exhibit a large 
          error rate in the single event effects (SEE) environment. 
          Analysis of data from a high-performance ADC demonstrates the 
          type of errors and their potential impact on system performance.

(93)  TI: SEU HARDENING OF FIELD-PROGRAMMABLE GATE ARRAYS (FPGAS) FOR SPACE 
          APPLICATIONS AND DEVICE CHARACTERIZATION
      AU: KATZ_R, BARTO_R, MCKERRACHER_P, KOGA_R
      NA: NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD,20771
          INTELSAT,PALO ALTO,CA,94303
          JOHNS HOPKINS UNIV,APPL PHYS LAB,LAUREL,MD,20723
          AEROSP CORP,EL SEGUNDO,CA,90245
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2179-2186
      AB: Field Programmable Gate Arrays (FPGAs) are being used in space 
          applications because of attractive attributes: good density, 
          moderate speed, low cost, and quick turn-around time. However, 
          these devices are susceptible to Single Event Upsets (SEUs). An 
          approach using triple modular redundancy (TMR) and feedback was 
          developed for flip-flop hardening in these devices. Test data 
          showed excellent results for this circuit topology. Total dose 
          and Single Event Effect (SEE) testing have been performed on 
          recently released technologies. Failures are analyzed and test 
          methodology is discussed.

(94)  TI: ION-INDUCED SUSTAINED HIGH-CURRENT CONDITION IN A BIPOLAR DEVICE
      AU: KOGA_R, FERRO_RJ, MABRY_DJ, PINKERTON_SD, ROMEO_DE, SCARPULLA_JR, 
          TSUBOTA_TK, SHOGA_M
      NA: AEROSP CORP,POB 92957,LOS ANGELES,CA,90009
          HUGHES SPACE & COMMUN,LOS ANGELES,CA,90009
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2172-2178
      AB: Observation of an ion-induced sustained high current condition 
          (''high current anomaly'') in a bipolar device, that is similar 
          but not identical to latchup, is reported. Both high current 
          anomaly and single event upset test results are presented for the 
          AD9048 test device. Photon emission microscopy was used to locate 
          the site of the high current anomaly. A model of the triggering 
          mechanism based on the results so obtained is described.
      KP: CMOS DEVICES, BREAKDOWN, LATCHUP

(95)  TI: EVIDENCE OF THE IONS IMPACT POSITION EFFECT ON SEB IN N-CHANNEL 
          POWER MOSFETS
      AU: DACHS_C, ROUBAUD_F, PALAU_JM, BRUGUIER_G, GASIOT_J, TASTET_P
      NA: UNIV MONTPELLIER 2,CTR ELECTR MONTPELLIER,F-34095 MONTPELLIER 
          05,FRANCE
          CTR NATL ETUD SPATIALES,F-31055 TOULOUSE,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2167-2171
      AB: Triggering of Single Event Burnout (SEB) in 
          Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs) is 
          studied by means of experiments and simulations based on real 
          structures. Conditions for destructive and nondestructive events 
          are investigated through current duration observations. The 
          effect of the ion's impact position is experimentally pointed 
          out. Finally, further investigation with 2D MEDICI simulations 
          [1] show that die different regions of the MOSFET cell indeed 
          exhibit different sensitivity with respect to burnout triggering.
      KP: SINGLE-EVENT BURNOUT

(96)  TI: EVALUATION OF SEGR THRESHOLD IN POWER MOSFETS
      AU: ALLENSPACH_M, BREWS_JR, MOURET_I, SCHRIMPF_RD, GALLOWAY_KF
      NA: UNIV ARIZONA,DEPT ELECT & COMP ENGN,TUCSON,AZ,85721
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2160-2166
      AB: Bias values, determined experimentally to result in single-event 
          gate rupture (SEGR) in power metal oxide semiconductor field 
          effect transistors (MOSFETs), are used in 2-D device simulations, 
          incorporating the experimental geometry. The simulations indicate 
          that very short time oxide field transients occur for ion strikes 
          when V-DS not equal OV. These transients can affect SEGR through 
          hole trapping and redistribution in the oxide.

(97)  TI: SINGLE-EVENT GATE RUPTURE IN VERTICAL POWER MOSFETS - AN ORIGINAL 
          EMPIRICAL EXPRESSION
      AU: WHEATLEY_CF, TITUS_JL, BURTON_DI
      NA: RR2 BOX 1120,DRUMS,PA,18222
          USN,CTR SURFACE WARFARE,CRANE,IN,47522
          HARRIS SEMICOND INC,MOUTAINTOP,PA,18707
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2152-2159
      AB: For the first time, an empirical expression is derived that 
          describes the susceptibility of a power double-diffused 
          metal-oxide semiconductor (DMOS) field-effect transistor (FET) to 
          single-event gate rupture (SEGR) induced by the interaction of 
          mono-energetic ions with regions of the n-epi, gate oxide, and 
          polysilicon gate. Using this expression, the failure threshold 
          voltages for the gate and drain can be analytically determined 
          for any particular value of energy deposition along the ion's 
          path or more commonly described as the ion's linear energy 
          transfer (LET) function. This paper delineates our research, an 
          in-depth study of vertical power DMOS transistors, having a 50-nm 
          gate oxide and a strong SEGR response, subjected to various 
          monoenergetic ions, representing particular values of LET between 
          0 and 83 MeV.cm(2) mg(-1). A description of the devices 
          characterized, the test setup and test methodology employed, the 
          failure threshold voltages measured, and the analysis techniques 
          used are all summarized. Finally, an empirical equation is 
          presented that portrays the locus of SEGR in the {-V-GS, V-DS} 
          plane for all values of LET.

(98)  TI: ESTIMATION OF 1-MEV EQUIVALENT NEUTRON FLUENCE FROM DOSIMETRY 
          RESPONSES WITHOUT SPECTRUM UNFOLDING
      AU: WILLIAMS_JG, GRIFFIN_PJ, KELLY_JG, FIGUEROA_JT
      NA: UNIV ARIZONA,TUCSON,AZ,85721
          SANDIA NATL LABS,ALBUQUERQUE,NM,87185
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2147-2151
      AB: The paper demonstrates the estimation of 1-MeV equivalent (Si) 
          neutron fluence from radiometric monitor data without prior 
          spectrum knowledge and without estimation of the neutron fluence 
          spectrum.

(99)  TI: ANALYTICAL AND EXPERIMENTAL DOSIMETRY TECHNIQUES FOR CALIBRATING 
          A LOW-ENERGY X-RAY-RADIATION SOURCE
      AU: BELLEM_RD, CRITCHFIELD_KL, PELZL_RM, PUGH_RD, TALLON_RW
      NA: EMBRY RIDDLE AERONAUT UNIV,DEPT ELECT ENGN,PRESCOTT,AZ,86301
          USAF,PHILLIPS LAB,SPACE & MISSILES TECHNOL 
          DIRECTORATE,MICROELECTR & PHOTON RES BRANCH,KIRTLAND AFB,NM,87117
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2139-2146
      AB: This paper describes the method used to calibrate a large-volume 
          continuous-wave x-ray radiation test chamber. The xray tube has a 
          tungsten target and emits a bremsstrahlung xray spectrum with end 
          point energies up to 160 keV. Analytical tools and experimental 
          dosimetry techniques were developed to map the radiation field 
          intensity and the resulting dose-deposition profiles in a variety 
          of materials throughout the chamber. Three detector types (x-ray 
          vacuum diodes, silicon PIN diodes, and PMOS FETs) were used to 
          measure spectral intensity and dose deposition in silicon 
          devices. CEPXS and PHOTCOEF electron-photon transport codes were 
          used to calculate the incident spectral energy distribution and 
          the energy deposition in the detector. Calculated and 
          experimental diode detector responses agreed to within 10 percent 
          over the full energy range. PMOS FETs were used to demonstrate 
          the correlation between total-dose-deposited in the x-ray chamber 
          and in the Cobalt-60 cell. The results of this effort provide 
          dosimetry and analysis tools needed to perform ionizing radiation 
          testing of large area (0.5m(2)) electronic subsystems.

(100) TI: FAST SHUTTER FOR LOW-BACKGROUND RADIATION ENVIRONMENTS AT SPR-III
      AU: KELLY_JG, SITES_KR, SCOTT_WH
      NA: SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM,87185
          SCI APPLICAT INT CORP,LAS VEGAS,NV,89109
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2125-2131
      AB: A fast shutter system has been developed to isolate experiments 
          from the radiation emitted after the main pulse of the Sandia 
          Pulsed Reactor, SPR III. In about 15 ms the system moves a 20 kg 
          shield in front of the beam port aperture in the facility shield 
          wall. A second gravity-driven shutter is dropped into place in 
          about 200 ms. The total attenuation achieved in the delayed beam 
          intensity is about a factor of one hundred. The shutter assembly 
          was used, along with a sensitive detection system, to observe the 
          gamma ray flux emitted by various materials activated by the 
          neutron beam at levels nine orders of magnitude smaller than the 
          gamma dose rate at the target during the reactor pulse.

(101) TI: PIN DIODE AND NEUTRON-SPECTRUM MEASUREMENTS AT THE ARMY PULSE 
          RADIATION FACILITY
      AU: OLIVER_MA
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2132-2138
      AB: Neutron spectrum measurements using the foil activation technique 
          have been made in two widely varying environments. One is an 
          extremely high neutron-to-gamma field and the other extremely 
          low. These measurements were used to characterize the fields and 
          tb evaluate the use of the DN-156 PIN diode for measuring 1 MeV 
          equivalent neutron fluence in silicon(Phi 1MeV(Si)). The 
          agreement between the Phi 1MeV(Si) as measured with diodes and as 
          determined by the spectral measurements was within +/-5%. A 
          proton recoil neutron spectrum measurement was also made in the 
          low gamma environment.

(102) TI: SOLID-STATE MICRODOSIMETER FOR RADIATION MONITORING IN SPACECRAFT 
          AND AVIONICS
      AU: ROTH_DR, MCNULTY_PJ, BEAUVAIS_WJ, REED_RA, STASSINOPOULOS_EG
      NA: CLEMSON UNIV,DEPT PHYS & ASTRON,CLEMSON,SC,29634
          NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD,20771
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2118-2124
      AB: An instrument is described which is designed to characterize the 
          complex radiation, environments inside spacecraft and airplanes 
          in terms of the risk of SEEs in the present and planned 
          microelectronic systems and in terms of the risk to flight crews 
          and passengers.
      KP: DOSIMETERS

(103) TI: 5-KEV TO 160-KEV CONTINUOUS-WAVE X-RAY SPECTRAL 
          ENERGY-DISTRIBUTION AND ENERGY FLUX-DENSITY MEASUREMENTS
      AU: TALLON_RW, KOLLER_DC, PELZL_RM, PUGH_RD, BELLEM_RD
      NA: USAF,PHILLIPS LAB,SPACE & MISSILES TECHNOL 
          DIRECTORATE,MICROELECTR & PHOTON RES BRANCH,KIRTLAND AFB,NM,87117
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2112-2117
      AB: Techniques developed for measuring the x-ray spectral energy 
          distribution (differential intensity) from a tungsten-target 
          bremsstrahlung x-ray source are reported. Spectra with end-point 
          energies ranging from 20 to 160 keV were recorded. A separate 
          effort to calibrate the dosimetry for the Phillips Laboratory 
          low-energy x-ray facility established a need to know the spectral 
          energy distributions at some point within the facility (previous 
          calibration efforts had relied on spectra obtained from computer 
          simulations). It was discovered that the primary discrepancy 
          between the simulated and measured spectra was in the L- and 
          K-line data. The associated intensity (energy flux density) of 
          the measured distributions was found to be up to 30% higher. 
          Based on the measured distributions, predicted device responses 
          were within 10% of the measured response as compared to about 30% 
          accuracy obtained with simulated distributions.

(104) TI: SINGLE-EVENT-INDUCED CHARGE COLLECTION AND DIRECT CHANNEL 
          CONDUCTION IN SUBMICRON MOSFETS
      AU: VELACHERI_S, MASSENGILL_LW, KERNS_SE
      NA: VANDERBILT UNIV,DEPT ELECT ENGN,NASHVILLE,TN,37235
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2103-2111
      AB: The single-event (SE) charge collection of an n-channel submicron 
          MOSFET is described using three dimensional device simulations. 
          Ion hits in the drain and in the channel region are considered. 
          For submicron MOSFETs, we show simulation evidence that there may 
          exist a direct source-drain conduction process induced by the 
          ion, called ion-triggered channeling (ITC), which may be an 
          important SE upset mechanism in deep submicron scaling. The 
          further study of increased ion-track-length to device-gate-length 
          ratios indicate that the direct source-drain conduction process 
          assumes increased importance for increased scaling.
      KP: DEVICES, CARRIERS, SILICON

(105) TI: ON THE ANGULAR-DEPENDENCE OF PROTON-INDUCED EVENTS AND CHARGE 
          COLLECTION
      AU: LEVINSON_J, BARAK_J, ZENTNER_A, AKKERMAN_A, LIFSHITZ_Y, 
          VICTORIA_M, HAJDAS_W, ALURRALDE_M
      NA: SOREQ NUCL RES CTR,IL-81800 YAVNE,ISRAEL
          PAUL SCHERRER INST,CH-5232 VILLIGEN,SWITZERLAND
          COMIS NACL ENERGIA ATOM,RA-8250 BUENOS AIRES,DF,ARGENTINA
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2098-2102
      AB: Careful measurements of the angular dependence of proton induced 
          SEU and SEL in HM65162 SRAMs and of energy deposited by protons 
          in thin surface barrier detectors are reported. We found a very 
          weak anisotropy whose behavior is described by our model.
      KP: CROSS-SECTIONS

(106) TI: SPICE ANALYSIS OF THE SEU SENSITIVITY OF A FULLY DEPLETED SOI 
          CMOS SRAM CELL
      AU: ALLES_ML
      NA: IBIS TECHNOL CORP,DANVERS,MA,01923
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2093-2097
      AB: SPICE analysis of SEU sensitivity of a 6-T SRAM cell using 
          commercially-representative fully depleted SOI CMOS technology 
          parameters indicates that reduction of the minority carrier 
          lifetime (parasitic bipolar gain) and use of thinner silicon can 
          significantly reduce SEU sensitivity.

(107) TI: 2-PARAMETER MODEL FOR PREDICTING SEU RATE
      AU: MIROSHKIN_VV, TVERSKOY_MG
      NA: PETERSBURG NUCL PHYS INST,GATCHINA,RUSSIA
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2085-2092
      AB: Two parameter model (volume and threshold energy) for describing 
          Single Event Upsets rate in memory devices is proposed. The 
          method of evaluation of these parameters is discussed. It is 
          shown that there is a good agreement between experimental and 
          calculated data.
      KP: SINGLE EVENT UPSET, PROTONS, SILICON

(108) TI: A NOVEL-APPROACH FOR MEASURING THE RADIAL-DISTRIBUTION OF CHARGE 
          IN A HEAVY-ION TRACK
      AU: HOWARD_JW, BLOCK_RC, DUSSAULT_H, STAPOR_WJ, MCDONALD_PT, 
          KNUDSON_AR, PINTO_MR
      NA: RENSSELAER POLYTECH INST,DEPT NUCL ENGN & ENGN PHYS,TROY,NY
          ROME LAB,ERDA,GRIFFISS AFB,NY
          USN,RES LAB,WASHINGTON,DC,20375
          AT&T BELL LABS,MURRAY HILL,NJ,07974
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2077-2084
      AB: We describe the design and uses of possible semiconductor test 
          structures for measuring the initial radial distribution of 
          charge and subsequent charge transport in a high energy, 
          heavy-ion track. Numerical simulations show how the test 
          structure can resolve different radial distributions of charge 
          within an ion track. The test structure simulations also show the 
          importance of accurately representing ion track structure in 
          single event effects simulations.

(109) TI: TOTAL-DOSE DEPENDENCE OF SOFT-ERROR HARDNESS IN 64KBIT SRAMS 
          EVALUATED BY SINGLE-ION MICROPROBE TECHNIQUE
      AU: MATSUKAWA_T, KISHIDA_A, TANII_T, KOH_M, HORITA_K, HARA_K, 
          SHIGETA_B, GOTO_M, MATSUDA_S, KUBOYAMA_S, OHDOMARI_I
      NA: WASEDA UNIV,SCH SCI & ENGN,SHINJUKU KU,3-4-1 OHKUBO,TOKYO 
          169,JAPAN
          WASEDA UNIV,KAGAMI MEM LAB MAT SCI & TECHNOL,SHINJUKU KU,TOKYO 
          169,JAPAN
          NATL SPACE DEV AGCY JAPAN,TSUKUBA SPACE CTR,TSUKUBA,IBARAKI 
          305,JAPAN
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2071-2076
      AB: Total dose effect on the soft-error susceptibility of 64kbit CMOS 
          SRAM has been investigated by using the single ion microprobe 
          technique which enables us to get a map of soft-error sensitivity 
          in a memory cell by hitting a micron-size area with single ions. 
          The effects of the ion dose on the susceptibility of each 
          error-sensitive site have been evaluated. The errors due to the 
          upset of p-MOSFETs have become more susceptible at higher dose 
          while that of the n-MOSFETs less susceptible. One of the origins 
          of the errors are the negative threshold voltage(V-th) shifts of 
          the MOSFETs which are caused by oxide trapped charges. 
          Displacement damage induced by ion irradiation also affects the 
          susceptibility to the soft-error.
      KP: EVENT UPSET, CMOS SRAMS, SENSITIVITY

(110) TI: CHARGE COLLECTION MECHANISMS OF HETEROSTRUCTURE FETS
      AU: MCMORROW_D, MELINGER_JS, THANTU_N, CAMPBELL_AB, WEATHERFORD_TR, 
          KNUDSON_AR, TRAN_LH, PECZALSKI_A
      NA: USN,RES LAB,WASHINGTON,DC,20375
          SFA INC,LANDOVER,MD,20785
          HONEYWELL INC,BLOOMINGTON,MN,55420
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2055-2062
      AB: Ion- and laser-induced charge-collection transients measured for 
          AlGaAs/InGaAs heterostructure insulated-gate field-effect 
          transistors (HIGFETs) reveal evidence for two mechanisms of 
          enhanced charge collection: a channel-modulation mechanism that 
          dominates the charge-collection processes at positive gate biases 
          and can persist for several nanoseconds; and a parasitic bipolar 
          transistor mechanism that shows a sensitive dependence on the 
          density of free carriers injected into the device, and is 
          complete within a few hundred picoseconds. The results reinforce 
          the utility of the laser technique for investigating the 
          charge-collection mechanisms of semiconductor devices.
      KP: GAAS-MESFETS

(111) TI: A NEW CLASS OF SINGLE EVENT HARD ERRORS
      AU: SWIFT_GM, PADGETT_DJ, JOHNSTON_AH
      NA: CALTECH,JET PROP LAB,4800 OAK GROVE DR,PASADENA,CA,91109
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2043-2048
      AB: Experimental results reported here indicate that heavy ions can 
          cause hard errors in conventional one-transistor dynamic memory 
          cells in addition to, as previously reported, four-transistor 
          static cells. Analysis of this data reveals that the hard errors 
          fall into two classes, one that is consistent with the expected 
          single-ion dose mechanism and another that is clearly 
          inconsistent. In particular, the new class of hard errors is 
          separable from the dosed cells based on irradiation conditions 
          and the data-loss time scale and direction. Further, this damage 
          is not additive between ion hits, does not follow ''effective'' 
          LET, and is quite resistant to annealing. As a result, these hard 
          errors would accumulate over long missions and, assuming the 
          damaged element is the access transistor, can be expected in 
          other types of storage elements with similar transistors, e.g., 
          static RAMs and microprocessor registers. Additionally, it was 
          found that scaling increases the susceptibility for a given ion 
          and lowers the ion threshold, although lowered bias mitigates the 
          damage.
      KP: HEAVY

(112) TI: IMPLICATIONS OF ANGLE OF INCIDENCE IN SEU TESTING OF MODERN 
          CIRCUITS
      AU: REED_RA, MCNULTY_PJ, ABDELKADER_WG
      NA: CLEMSON UNIV,DEPT PHYS & ASTRON,CLEMSON,SC,29634
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2049-2054
      AB: Simulations show that ignoring the angular dependence of proton 
          SEU cross sections produces errors in predictions of SEU rates in 
          space. Moreover, they suggest that devices with thin sensitive 
          volumes may upset to protons at grazing incidence despite high 
          threshold LET values (>80 MeV cm(2)) at normal incidence. 
          Incorporating angular effects in space predictions requires 
          accurate knowledge of the dimensions of the sensitive volume 
          associated with the SEU-sensitive junction, especially the 
          thickness. A method is proposed for using proton SEU measurements 
          at different angles and energies combined with simulations to 
          determine the thickness of the sensitive volume and to test the 
          reliability of the predictions.
      KP: SINGLE EVENT UPSETS

(113) TI: A PROPOSED SEU TOLERANT DYNAMIC RANDOM-ACCESS MEMORY (DRAM) CELL
      AU: AGRAWAL_GR, MASSENGILL_LW, GULATI_K
      NA: VANDERBILT UNIV,DEPT ELECT & COMP ENGN,221 KIRKLAND 
          HALL,NASHVILLE,TN,37232
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2035-2042
      AB: A novel DRAM cell technology consisting of an n-channel access 
          transistor and a bootstrapped storage capacitor with an 
          integrated breakdown diode is proposed. This design offers 
          considerable resistance to single event cell errors; The 
          informational charge packet is shielded from the single event by 
          placing the vulnerable node in a self-compensating state while 
          the cell is in standby mode. The proposed cell is comparable in 
          size to a conventional DRAM cell, and computer simulations show 
          an improvement in critical charge of two orders of magnitude over 
          Conventional 1-T DRAM cells.
      PA: 4864374 US;BANERJEE_SK{1989
          5234856 US;GONZALEZ{1993}
          5236858 US;LEE{1993}
          5252845 US;CHEON{1993}

(114) TI: SINGLE EVENT MIRRORING AND DRAM SENSE AMPLIFIER DESIGNS FOR 
          IMPROVED SINGLE-EVENT-UPSET PERFORMANCE
      AU: GULATI_K, MASSENGILL_LW, AGRAWAL_GR
      NA: VANDERBILT UNIV,DEPT ELECT & COMP ENGN,221 KIRKLAND 
          HALL,NASHVILLE,TN,37235
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2026-2034
      AB: This paper proposes and investigates schemes for hardening the 
          conventional CMOS cross-coupled DRAM sense amplifier to single 
          event upset (SEU). These schemes, adapted from existing SRAM 
          hardening techniques, ate intended to harden the dynamic random 
          access memory to bitline-mode errors during the sensing period. 
          Simulation results indicate that a 9k Omega L-resistor hardening 
          scheme provides greater than 24-fold improvement in critical 
          charge over a significant part of the sensing period. Also 
          proposed is a novel single event (SE) mirroring concept for SEU 
          hardening of DRAMs. This concept has been implemented for 
          hardening the bitlines to hits on diffusion regions connected to 
          the lines during the highly susceptible high-impedance state of 
          the bitlines, It is shown to result in over 26-fold improvement 
          in the level of critical charge using a 2pF dynamic capacitive 
          coupling.
      PA: 342466;SMITH_F{1989
          4805148 US;DIEHLNAGLE_SE{1989}
          4809226 US;OCHOA{1989}
      KP: MEMORY CELLS, SOFT ERRORS, CMOS, SRAM, CIRCUIT, RAMS

(115) TI: HIGH-ENERGY HEAVY-ION-INDUCED SINGLE EVENT TRANSIENTS IN 
          EPITAXIAL STRUCTURES
      AU: DUSSAULT_H, HOWARD_JW, BLOCK_RC, PINTO_MR, STAPOR_WJ, KNUDSON_AR
      NA: RENSSELAER POLYTECH INST,DEPT NUCL ENGN & ENGN PHYS,TROY,NY,12180
          ROME LAB,ERDA,GRIFFISS AFB,NY,13441
          AT&T BELL LABS,MURRAY HILL,NJ,07974
          USN,RES LAB,WASHINGTON,DC,20375
          SACHS FREEMAN ASSOCIATES INC,LANDOVER,MD,20785
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2018-2025
      AB: This paper describes numerical and experimental heavy-ion charge 
          collection studies using P+N junctions on epitaxial layers. The 
          numerical simulations provide insights into the basic mechanisms 
          contributing to transient currents and charge collection in 
          devices on epitaxial layers. This paper also presents charge 
          collection data from similar to 2 GeV I-127 ions incident upon 
          P+N junctions on both bulk silicon and epitaxial layers and 
          compares the experimental data with the simulation results. The 
          experimental data show that charge deposited below the epitaxial 
          layer can be collected. This work is unique and important because 
          this GeV-energy-range I-127 ion more nearly represents a cosmic 
          ray compared to lower energy, heavy-ions in the hundreds of MeV 
          energy range. This paper also discusses the simulation results 
          with respect to the experimental data and charge collection 
          models for epitaxial transistors. Additionally, a shunting model 
          is proposed to model the early transient current responses.
      KP: CHARGE COLLECTION, CMOS LATCHUP, MODEL

(116) TI: 3-DIMENSIONAL SIMULATION OF CHARGE COLLECTION AND MULTIPLE-BIT 
          UPSET IN SI DEVICES
      AU: DODD_PE, SEXTON_FW, WINOKUR_PS
      NA: SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM,87185
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2005-2017
      AB: In this paper, three-dimensional numerical simulation is used to 
          explore the basic charge-collection mechanisms in silicon n(+)/p 
          diodes. For diodes on lightly-doped substrates (<1x10(15) cm(-3)) 
          struck by a 100-MeV Fe ion, the funneling effect is very strong 
          and essentially all collection is by funnel-assisted drift. This 
          drift collection may occur as late as several nanoseconds after 
          the strike, later than is usually associated with drift 
          collection. For moderately doped substrates (=1x10(16) cm(-3)) 
          and epitaxial structures grown on heavily-doped substrates, the 
          funnel effect is weaker and drift and diffusion are of more equal 
          importance. For 5-MeV He (alpha-particle) strikes with 
          low-density charge tracks, the charge-collection transient 
          exhibits both drift and diffusion regimes regardless of the 
          substrate doping. Simulations of diodes with passive external 
          loads indicate that while the current response is altered 
          considerably by the load, total collected charge is not greatly 
          affected for the simple resistive loads studied. 
          Three-dimensional mixed-mode simulation is performed to 
          investigate charge-collection behavior and upset mechanisms in 
          complete CMOS SRAM cells. Simulations of double SRAM cell 
          structures indicate that only collection by diffusion from 
          ''between-node'' strikes is capable of producing multiple-bit 
          upsets in the simulated technology. Limitations of the 
          simulations, specifically carrier-carrier scattering models and 
          large concentration gradients, are also discussed.
      KP: SINGLE-EVENT, NUMERICAL-SIMULATION, ION TRACKS, SILICON, SEU, 
          ERRORS, TRANSPORT, CIRCUIT, MODEL, SRAMS

(117) TI: SINGLE EVENT EFFECT GROUND TEST-RESULTS FOR A FIBER OPTIC DATA 
          INTERCONNECT AND ASSOCIATED ELECTRONICS
      AU: LABEL_KA, HAWKINS_DK, COOLEY_JA, SEIDLECK_CM, MARSHALL_P, DALE_C, 
          GATES_MM, KIM_HS, STASSINOPOULOS_EG
      NA: NASA,GODDARD SPACE FLIGHT CTR,HUGHES ST SYST CORP,CODE 
          7351,GREENBELT,MD,20771
          NRL,SFA,WASHINGTON,DC
          NASA,GODDARD SPACE FLIGHT CTR,JACKSON & TULL,GREENBELT,MD,20771
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1999-2004
      AB: As spacecraft unlock the potential of fiber optics for 
          spaceflight applications, system level bit error rates become of 
          concern to the system designer. We present ground test data and 
          analysis on candidate system components.

(118) TI: DARK CURRENT-INDUCED IN LARGE CCD ARRAYS BY PROTON-INDUCED 
          ELASTIC REACTIONS AND SINGLE TO MULTIPLE-EVENT SPALLATION 
          REACTIONS
      AU: CHEN_L, MCNULTY_PJ, LARSON_S, THOMPSON_DA, MILLER_TL, LEE_T
      NA: CLEMSON UNIV,DEPT PHYS & ASTRON,CLEMSON,SC,29634
          EASTMAN KODAK CO,ROCHESTER,NY,14650
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1992-1998
      AB: Computer simulations of the non-ionizing energy loss deposited in 
          sensitive volumes as a result of proton-induced spallation 
          reactions agree with analytic models for large sensitive volumes 
          exposed to high fluence. They predict unique features for small 
          volumes and low-fluence exposures which are observed in exposures 
          of large arrays of CCD pixels. Calculations of the number of 
          spallation reactions per pixel correlate with the recently 
          reported relative frequency of switching dark-current states.
      KP: INDUCED DISPLACEMENT DAMAGE, SILICON

(119) TI: PROTON-INDUCED CHARGE-TRANSFER DEGRADATION IN CCDS FOR NEAR-ROOM 
          TEMPERATURE APPLICATIONS
      AU: HOPKINS_IH, HOPKINSON_GR, JOHLANDER_B
      NA: SIRA,UCL,POSTGRAD CTR,SOUTH HILL,CHISLEHURST BR7 5EH,KENT,ENGLAND
          SIRA INST LTD,CHISLEHURST BR7 5EH,KENT,ENGLAND
          EUROPEAN SPACE AGCY,ESTEC,2200 AG NOORDWIJK,NETHERLANDS
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1984-1991
      AB: An optical technique for measuring charge transfer inefficiency 
          (CTI) in CCDs, operated under near-room temperature, high readout 
          rate conditions, is described. It is possible to measure trap 
          emission times and CTI dependence on signal size, background 
          charge and clock waveform shape to high accuracy, both for serial 
          and parallel transfers. It is shown that the presence of 
          background charge (or 'fat zero') can substantially improve 
          charge transfer efficiency.
      KP: COUPLED-DEVICES, DAMAGE

(120) TI: A COMPARISON OF MONTE-CARLO AND ANALYTIC TREATMENTS OF 
          DISPLACEMENT DAMAGE IN SI MICROVOLUMES
      AU: DALE_CJ, CHEN_L, MCNULTY_PJ, MARSHALL_PW, BURKE_EA
      NA: USN,RES LAB,WASHINGTON,DC,20375
          CLEMSON UNIV,CLEMSON,SC,29634
          SFA INC,LANDOVER,MD,20785
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1974-1983
      AB: In this paper, we compare Monte Carlo and analytic calculations 
          of displacement damage resulting from inelastic proton reactions 
          in Si. These comparisons include the nonionizing energy loss 
          rate, the mean recoil damage energy spectra, and their associated 
          variance. In the limit of bulk material, both approaches are in 
          good agreement. sensitive volumes shrink and incident proton 
          energies increase, the ranges of the spallation recoil fragments 
          approach the smallest dimension of the microvolume, and the 
          pixel-to-pixel damage variance increases rapidly. In this regime, 
          a Monte Carlo approach is used to describe the damage energy 
          distribution. Indeed, we show that such simulations predict the 
          63 MeV proton-induced dark current histograms more accurately 
          than present analytic methods.
          The Monte Carlo code is also used to explore ground test fidelity 
          issues for devices with small sensitive volumes.
      KP: ENERGY-DEPENDENCE, SILICON, EXTREMES, NUCLEAR, PROTONS

(121) TI: PARTICLE-INDUCED BIT ERRORS IN HIGH-PERFORMANCE FIBER OPTIC DATA 
          LINKS FOR SATELLITE DATA MANAGEMENT
      AU: MARSHALL_PW, DALE_CJ, CARTS_MA, LABEL_KA
      NA: USN,RES LAB,WASHINGTON,DC,20375
          SFA INC,LANDOVER,MD,20785
          NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD,20771
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1958-1965
      AB: Experimental test methods and analysis tools are demonstrated to 
          assess particle-induced bit errors on fiber optic link receivers 
          for satellites. Susceptibility to direct ionization from low LET 
          particles is quantified by analyzing proton and helium ion data 
          as a function of particle LET. Existing single event analysis 
          approaches are shown to apply, with appropriate modifications, to 
          the regime of temporally (rather than spatially) distributed 
          bits, even though the sensitivity to single events exceeds 
          conventional memory technologies by orders of magnitude. The 
          cross-section LET dependence follows a Weibull distribution at 
          data rates from 200 to 1000 Mbps and at various incident optical 
          power levels. The LET threshold for errors is shown, through both 
          experiment and modeling, to be 0 in all cases! The error 
          cross-section exhibits a strong inverse dependence on received 
          optical power in the LET range where most orbital single events 
          would occur, thus indicating that errors can be minimized by 
          operating links with higher incident optical power. Also, an 
          analytic model is described which incorporates the appropriate 
          physical characteristics of the link as well as the optical and 
          receiver electrical characteristics. Results indicate appropriate 
          steps to assure suitable link performance even in severe particle 
          orbits.

(122) TI: TOTAL, DOSE AND PROTON TESTING OF A COMMERCIAL HGCDTE ARRAY
      AU: HOPKINSON_GR, BADDILEY_CJ, GUY_DRP, PARSONS_JE
      NA: SIRA INST LTD,SOUTH HILL,CHISLEHURST BR7 5EH,KENT,ENGLAND
          DRA,ELECTR SECTOR,MALVERN WR14 3PS,WORCS,ENGLAND
          GEC MARCONI INFRARED LTD,SOUTHAMPTON SO9 7QG,HANTS,ENGLAND
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1966-1973
      AB: The radiation tolerance of a commercially available 256x4 HgCdTe 
          array has been measured. The main effects were ionization-induced 
          and produced changes in diode slope resistance and CMOS 
          multiplexer characteristics (particularly the onset of parasitic 
          leakage currents after similar to 15krad(Si). However these 
          effects annealed with storage above 20 degrees C.

(123) TI: RADIATION EFFECTS ON FUSED BICONICAL TAPER WAVELENGTH-DIVISION 
          MULTIPLEXERS
      AU: GUTIERREZ_RC, SWIFT_GM, DUBOVITSKY_S, BARTMAN_RK, BARNES_CE, 
          DORSKY_L
      NA: CALTECH,JET PROP LAB,4800 OAK GROVE DR,PASADENA,CA,91109
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1950-1957
      AB: The effects of radiation on fused biconical taper wavelength 
          division multiplexers are presented. A theoretical model 
          indicates that index changes in the fiber are primarily 
          responsible for the degradation of these devices.
      KP: REFRACTIVE-INDEX, COUPLERS, DEPENDENCE, FIBERS

(124) TI: CO-60 GAMMA-RAY AND ELECTRON DISPLACEMENT DAMAGE STUDIES OF 
          SEMICONDUCTORS
      AU: XAPSOS_MA, SUMMERS_GP, BLATCHLEY_CC, COLERICO_CW, BURKE_EA, 
          MESSENGER_SR, SHAPIRO_P
      NA: USN,RES LAB,WASHINGTON,DC,20375
          UNIV MARYLAND,DEPT PHYS,BALTIMORE,MD,21228
          SPIRE CORP,BEDFORD,MA,01730
          SFA INC,LANDOVER,MD,20785
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1945-1949
      AB: A general method for relating Co-60 gamma ray and monoenergetic 
          electron beam displacement damage is presented. The approach is 
          based on the concept of effective ''displacement damage dose'', 
          which is analogous to ideas used to study ionizing radiation 
          effects. The response to electron damage of p-type gallium 
          arsenide and indium phosphide solar cells, as previously reported 
          for p-type silicon solar cells, is proportional to the square of 
          the nonionizing energy loss.

(125) TI: A MOBILITY STUDY OF THE RADIATION-INDUCED ORDER EFFECT IN 
          GALLIUM-ARSENIDE
      AU: JORIO_A, PARENTEAU_M, AUBIN_M, CARLONE_C, KHANNA_SM, GERDES_JW
      NA: UNIV SHERBROOKE,DEPT PHYS,SHERBROOKE,PQ J1K 2R1,CANADA
          DEF RES ESTAB,OTTAWA,ON K1A 0Z4,CANADA
          USA,PULSE RADIAT FACIL,ABERDEEN PROVING GROUND,MD,21005
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1937-1944
      AB: N-type gallium arsenide doped with silicon was irradiated with 
          reactor neutrons to 10(12), 3x10(12), 10(13), 3x10(13), 10(14), 
          3x10(14), 10(15), and 3x10(15) cm(-2) (1 MeV equivalent fluence). 
          The temperature dependence of the mobility was obtained after 
          irradiation and annealing to 550 degrees C for 30 minutes. The 
          maximum value of the mobility, mu(max), with respect to 
          temperature was obtained as a function of fluence. For samples 
          which have been irradiated and then annealed, mu(max) goes 
          through a maximum at a fluence of 10(13) cm(-2) and is 10% higher 
          than in the unirradiated samples. At higher fluences, the 
          mobility degrades. We attribute the increase in mobility at lower 
          fluences to a radiation induced order effect. The disappearance 
          of the deep level EL12 could be associated with this effect. At 
          higher fluences where the mobility degrades, we observe by 
          photoluminescence spectroscopy, the gallium vacancy, a point 
          defect introduced by the irradiation, and the transfer of the 
          silicon atom from the gallium site to the arsenic site. This 
          suggests that growth of the gallium vacancy or the silicon at the 
          arsenic site can be associated with mobility degradation.
      KP: NEUTRON-IRRADIATED GAAS

(126) TI: PARAMETER-FREE, PREDICTIVE MODELING OF SINGLE EVENT UPSETS DUE TO 
          PROTONS - NEUTRONS, AND PIONS IN TERRESTRIAL COSMIC-RAYS
      AU: SRINIVASAN_GR, TANG_HK, MURLEY_PC
      NA: IBM CORP,CTR SEMICOND RES & DEV,HOPEWELL JCT,NY,12533
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2063-2070
      AB: In this paper we present a new approach and a computer software 
          for modeling single event upsets. This model, named Soft Error 
          Montecarlo Model (SEMM), does not need any experimental inputs or 
          any parameter fitting. It is intended to be a design tool for 
          chip designers when they want to optimize their designs for soft 
          error hardness and performance. The paper focuses on terrestrial 
          cosmic rays that cause single event upsets. Details of the 
          nuclear modeling and of the coupled device-circuit modeling are 
          presented. Also presented are the comparison of SEMM predictions 
          against measurements of single event upset rate in proton beam 
          experiments and in computer main frame field tests performed at 
          high ground elevations. We also present some proton-pion 
          comparisons that are relevant to single event upsets.
      KP: SILICON

(127) TI: STUDY OF THE DEFECTS INDUCED IN N-TYPE SILICON IRRADIATED BY 
          1-3-MEV PROTONS
      AU: NTSOENZOK_E, BARBOT_JF, DESGARDIN_P, VERNOIS_J, BLANCHARD_C, 
          ISABELLE_DB
      NA: CERI,CNRS,3A RUE FEROLLERIE,F-45071 ORLEANS,FRANCE
          LAB MET PHYS,URA 131,F-86022 POITIERS,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1932-1936
      AB: The electrical properties of semiconductor components can be 
          greatly modified by proton implantation. Spreading resistance, 
          C-V (capacitance voltage) and DLTS (deep levels transient 
          spectroscopy) measurements have been used to characterize N-type 
          silicon irradiated by MeV proton at fluences up to 
          10(14)p(+)cm(-2). The greatest drawback induced by proton 
          implantation is the overdoping effect which can strongly reduce 
          device efficiency. The present work reports this effect in both 
          annealed and unannealed samples.
      KP: COMPLETE ELECTRICAL CHARACTERIZATION

(128) TI: ON THE IMPACT OF LOW FLUENCE IRRADIATION WITH MEV PARTICLES ON 
          SILICON DIODE CHARACTERISTICS AND RELATED MATERIAL PROPERTIES
      AU: VANHELLEMONT_J, SIMOEN_E, CLAEYS_C, KANIAVA_A, GAUBAS_E, BOSMAN_G, 
          JOHLANDER_B, ADAMS_L, CLAUWS_P
      NA: IMEC,KAPELDREEF 75,B-3001 LOUVAIN,BELGIUM
          VILNIUS STATE UNIV,VILNIUS 2054,LITHUANIA
          UNIV FLORIDA,GAINESVILLE,FL,32611
          EUROPEAN SPACE AGCY,ESTEC,2200 AG NOORDWIJK,NETHERLANDS
          STATE UNIV GHENT,B-9000 GHENT,BELGIUM
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1924-1931
      AB: The electrical activity of MeV particle irradiation induced 
          lattice defects in silicon, is studied through their impact on 
          diode characteristics and on minority carrier lifetime. For the 
          first time results are presented on low-frequency noise 
          spectroscopy for radiation damage and substrate characterisation.
          The results show that diodes on Cz substrates are more radiation 
          hard than on epi- and FZ substrates but have a poorer quality 
          before irradiation with respect to noise, minority carrier 
          lifetime and I/V characteristics.
      KP: CF-252

(129) TI: RADIATION-INDUCED DEFECT INTRODUCTION RATES IN SEMICONDUCTORS
      AU: DREVINSKY_PJ, FREDERICKSON_AR, ELSAESSER_DW
      NA: USAF,PHILLIPS LAB,29 RANDOLPH RD,BEDFORD,MA,01731
          USAF,ROME LAB,BEDFORD,MA,01731
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1913-1923
      AB: The defect introduction rate at 295K by 1-MeV electrons in the 
          p-side of n(+)-p silicon junctions under various applied voltages 
          was measured using both DLTS and C-V techniques. The introduction 
          rate of most defects is a strong function of applied bias and 
          distance from the junction. Open circuit irradiation produces the 
          smallest introduction rate while reverse bias enhances the rate 
          by a factor of five for most defects. The C-V technique finds 
          three times the concentration of defects that the DLTS technique 
          finds. The C-V technique cannot distinguish types of defects: it 
          sums all defects. Heavy reverse bias irradiations produced 
          unstable junctions that could be partially restabilized by 
          further opera circuit irradiations. The electron-hole pairs 
          generated by the irradiation appear to play a major role in the 
          development of the final defect population resulting from the 
          same irradiation. Even in a short irradiation, defects initially 
          created early in the irradiation are altered or annealed by 
          continued irradiation. Recombination-enhanced diffusion theory 
          appears to explain some of the results and, therefore, may be an 
          important factor in the defect introduction process in many 
          semiconductors.
      KP: SILICON, CARBON, DAMAGE

(130) TI: DETERMINATION OF THE FERMI-LEVEL POSITION FOR NEUTRON-IRRADIATED 
          HIGH-RESISTIVITY SILICON DETECTORS AND MATERIALS USING THE 
          TRANSIENT CHARGE TECHNIQUE (TCHT)
      AU: EREMIN_V, LI_Z
      NA: BROOKHAVEN NATL LAB,UPTON,NY,11973
          RUSSIAN ACAD SCI,AF IOFFE PHYSICOTECH INST,ST PETERSBURG 
          196140,RUSSIA
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1907-1912
      AB: The transient charge technique (TChT) has been used in this work 
          to study the electrical properties in both space charge region 
          (SCR) and electrical neutral bulk (ENB) of neutron irradiated 
          high resistivity (4-6 k Omega-cm) silicon particle detectors. 
          Detectors irradiated to various neutron fluences were measured by 
          TChT at various biases and temperatures from 110 K to 300 K. The 
          Fermi level, obtained from the Arrhenius plot of the time 
          constant of the ohmic relaxation component of the charge shape, 
          has been found to stabilize around E(c)-0.47 to 0.50 eV at high 
          fluences (Phi(n)>10(13) n/cm(2)).
      KP: RADIATION

(131) TI: INVESTIGATION OF POSSIBLE SOURCES OF 1/F NOISE IN IRRADIATED 
          N-CHANNEL POWER MOSFETS
      AU: PLOOR_MD, SCHRIMPF_RD, GALLOWAY_KF
      NA: INTEL CORP,CHANDLER,AZ,85226
          UNIV ARIZONA,DEPT ELECT & COMP ENGN,TUCSON,AZ,85721
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1902-1906
      AB: 1/f noise in irradiated n-channel power MOSFETs is compared to 
          interface- and oxide-trapped charge densities. The noise follows 
          the bias dependences predicted by an equation based on the number 
          fluctuation model derived for noise in the saturation region. The 
          magnitude of the noise switched between two distinct levels when 
          the bias was reversed during post-irradiation annealing. The 
          noise did not correlate well with interface traps or oxide 
          trapped charge. Border traps provide a reasonable explanation, 
          with charge compensation being an important effect. During 
          positive-bias annealing, near-interfacial traps are compensated 
          and no longer contribute to the 1/f noise. However, when the bias 
          is reversed, the traps are decompensated and the noise increases 
          again.
      KP: OXIDE-SEMICONDUCTOR DEVICES, RADIATION-INDUCED CHARGE, 
          INTERFACE TRAPS, MOS DEVICES, BORDER TRAPS, TRANSISTORS

(132) TI: EFFECT OF JUNCTION FRINGING FIELD ON RADIATION-INDUCED LEAKAGE 
          CURRENT IN OXIDE ISOLATION STRUCTURES AND NONUNIFORM DAMAGE NEAR 
          THE CHANNEL EDGES IN MOSFETS
      AU: PERSHENKOV_VS, CHIROKOV_MS, BRETCHKO_PT, FASTENKO_PO, BAEV_VK, 
          BELYAKOV_VV
      NA: MOSCOW ENGN PHYS INST,DEPT MICROELECTR,MOSCOW 115409,RUSSIA
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1895-1901
      AB: A significant contribution of fringing field effect on 
          radiation-induced leakage current in oxide isolation structure 
          and damage nonuniformity in MOSFET was demonstrated using 
          analytical expressions for electrical field.
          A two dimensional analytical model describing electrical field 
          distribution in oxide isolation and MOSFET structures was 
          elaborated to provide the dynamics of positive oxide trapped 
          charge build-up process. The leakage current at the bottom of the 
          recessed field oxide calculation was performed using oxide 
          trapped charge density profile obtained through charge build-up 
          process simulated applying electrical field model to changing 
          conditions during irradiation process. Calculations are presented 
          for leakage current versus dose dependencies for different 
          structure dimensions and irradiation conditions; leakage current 
          versus voltage shift of buried layer during irradiation ana 
          P+-channel stop region doping level; and I-V characteristics of 
          parasitic transistor. Experimental data concerning damage 
          nonuniformity are discussed together with calculated data for 
          electrical field pattern and nonuniformity length in MOSFETs.

(133) TI: SEU IMMUNITY - THE EFFECTS OF SCALING ON THE PERIPHERAL CIRCUITS 
          OF SRAMS
      AU: JACUNSKI_L, DOYLE_S, JALLICE_D, HADDAD_N, SCOTT_T
      NA: LORAL FED SYST MANASSAS,9500 GODWIN DR,MANASSAS,VA,22110
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2272-2276
      AB: Heavy ion testing on a scaled 256K SRAM has shown that SEU 
          analysis of the peripheral circuits as well as the memory cell 
          must be performed as circuits are scaled to smaller and smaller 
          dimensions. This paper describes the SEU induced phenomena 
          experienced by the scaled version of a previous 256K radiation 
          hardened SRAM design, affected by circuits in the periphery.
      PA: 4996670 US;CIRAULA_M{1991}

(134) TI: ANALYSIS OF NEUTRON DAMAGE IN HIGH-TEMPERATURE SILICON-CARBIDE 
          JFETS
      AU: MCLEAN_FB, MCGARRITY_JM, SCOZZIE_CJ, TIPTON_CW, DELANCEY_WM
      NA: USA,RES LAB,2800 POWDER MILL RD,ADELPHI,MD,20783
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1884-1894
      AB: Neutron-induced displacement damage effects in n-channel, 
          depletion-mode junction-field-effect transistors (JFETs) 
          fabricated on 6H-silicon carbide are reported as a function of 
          temperature from room temperature (RT) to 300 degrees C. The data 
          are analyzed in terms of a refined model that folds in recently 
          reported information on the two-level ionization energy structure 
          of the nitrogen donors. A value of 5 +/- 1 cm(-3) per n/cm(2) is 
          obtained for the deep-level defect introduction rate induced by 
          the neutron irradiation. Due to partial ionization of the donor 
          atoms at RT, the carrier removal rate is a function of 
          temperature, varying from 3.5 cm(-1) at RT to 4.75 cm(-1) at 300 
          degrees C. The relative neutron effect on carrier mobility varies 
          with temperature approximately as T--7/2, dropping by an order of 
          magnitude at 300 degrees C compared with the RT effect. The 
          results offer further support for the use of SIC devices in 
          applications which combine high-temperature and severe radiation 
          environments, where the use of Si and GaAs technologies is 
          limited.

(135) TI: BOUNDING THE TOTAL-DOSE RESPONSE OF MODERN BIPOLAR-TRANSISTORS
      AU: KOSIER_SL, COMBS_WE, WEI_A, SCHRIMPF_RD, FLEETWOOD_DM, DELAUS_M, 
          PEASE_RL
      NA: VTC INC,BLOOMINGTON,MN,55425
          UNIV ARIZONA,DEPT ECE,TUCSON,AZ,85721
          USN,SURFACE WARFARE CTR CRANE,CRANE,IN,47522
          ANALOG DEVICES INC,WILMINGTON,MA,01887
          RLP RES,ALBUQUERQUE,NM,87122
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1864-1870
      AB: The excess base current in an irradiated BJT increases 
          superlinearly with total dose at low-total-dose levels. In this 
          regime, the excess base current depends on the particular 
          charge-trapping properties of the oxide that covers the 
          emitter-base junction. The device response is dose-rate-, 
          irradiation-bias-, and technology-dependent in this regime. 
          However, once a critical amount of charge has accumulated in the 
          oxide, the excess base current saturates at a value that is 
          independent of how the charge accumulated. This saturated excess 
          base current depends on the device layout, bulk lifetime in the 
          base region, and the measurement bias. In addition to providing 
          important insight into the physics of bipolar-transistor 
          total-dose response, these results have significant circuit-level 
          implications. For example, in some circuits, the transistor gain 
          that corresponds to the saturated excess base current is 
          sufficient to allow reliable circuit operation. For cases in 
          which the saturated value of current gain is acceptable, and 
          where other circuit elements permit such over-testing, this can 
          greatly simplify hardness assurance for space applications.

(136) TI: SPACE RADIATION EVALUATION OF 16-MBIT DRAMS FOR MASS MEMORY 
          APPLICATIONS
      AU: CALVEL_P, LAMOTHE_P, BARILLOT_C, ECOFFET_R, DUZELLIER_S, 
          STASSINOPOULOS_EG
      NA: ALCATEL ESPACE,26 AV JF CHAMPOLL,BP 1187,F-31037 TOULOUSE,FRANCE
          CNES,F-31035 TOULOUSE,FRANCE
          CERT,DERTS,F-31035 TOULOUSE,FRANCE
          NASA,GODDARD SPACE FLIGHT CTR,GREENBELT,MD,20771
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2267-2271
      AB: This paper presents heavy ions, protons and total dose data 
          results for 16 Mbit DRAMs from IBM and TEXAS INSTRUMENTS, 
          including a 'built-in ECC' DRAM. Single Event Phenomena rate are 
          calculated for low earth orbits.

(137) TI: RADIATION EFFECTS IN OXYNITRIDES GROWN IN N2O
      AU: SAKS_NS, SIMONS_M, FLEETWOOD_DM, YOUNT_JT, LENAHAN_PM, KLEIN_RB
      NA: USN,RES LAB,WASHINGTON,DC,20375
          RES TRIANGLE INST,RES TRIANGLE PK,NC,27709
          SANDIA NATL LABS,ALBUQUERQUE,NM,87185
          PENN STATE UNIV,UNIVERSITY PK,PA,16802
          SFA INC,LANDOVER,MD,20785
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1854-1863
      AB: Oxynitrides have been grown by oxidation in N2O in a standard 
          thermal oxidation furnace. Two N2O processes have been studied: 
          oxidation in N2O only, and two-step oxidation with initial 
          oxidation in O-2 followed by oxidation/nitridation in N2O. 
          Results are presented for radiation damage at 80 and 295K, hole 
          trapping, interface trap creation, electron spin resonance, and 
          hole de-trapping using thermally-stimulated current analysis. N2O 
          oxynitrides do not appear to have the well-known. drawbacks of 
          NH3-annealed oxynitrides. Creation of interface traps during 
          irradiation is reduced in the N2O oxynitrides, with the degree of 
          improvement depending on the fabrication process.
      KP: INTERFACIAL NITROGEN, NITRIDED OXIDES, SIO2, FIELD, BREAKDOWN, 
          MOSFETS, CHARGE, HARD

(138) TI: PHYSICAL-MECHANISMS CONTRIBUTING TO ENHANCED BIPOLAR GAIN 
          DEGRADATION AT LOW-DOSE RATES
      AU: FLEETWOOD_DM, KOSIER_SL, NOWLIN_RN, SCHRIMPF_RD, REBER_RA, 
          DELAUS_M, WINOKUR_PS, WEI_A, COMBS_WE, PEASE_RL
      NA: SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM,87185
          UNIV ARIZONA,DEPT ECE,TUCSON,AZ,85721
          PHILLIPS LAB,VTE,ALBUQUERQUE,NM,87185
          ANALOG DEVICES INC,WILMINGTON,MA,01887
          USN,CTR SURFACE WARFARE,CRANE,IN,47522
          RLP RES INC,ALBUQUERQUE,NM,87122
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1871-1883
      AB: We have performed capacitance-voltage (C-V) and 
          thermally-stimulated-current (TSC) measurements on 
          non-radiation-hard MOS capacitors simulating screen oxides of 
          modern bipolar technologies. For 0-V irradiation at similar to 25 
          degrees C, the net trapped-positive-charge density (N-ox) 
          inferred from midgap C-V shifts is similar to 25-40% greater for 
          low-dose-rate (< 10 rad(SiO2)/s) than for high-dose-rate (> 100 
          rad(SiO2)/s) exposure. Device modeling shows that such a 
          difference in screen-oxide N-ox is enough to account for the 
          enhanced low-rate gain degradation often observed in bipolar 
          devices, due to the similar to exp (N-ox(2)) dependence of the 
          excess base current. At the higher rates, TSC measurements reveal 
          a similar to 10% decrease in trapped-hole density over low rates. 
          Also, at high rates, up to similar to 2.5-times as many trapped 
          holes are compensated by electrons in border traps than at low 
          rates for these devices and irradiation conditions. Both the 
          reduction in trapped-hole density and increased charge 
          compensation reduce the high-rate midgap shift. A physical model 
          is developed which suggests that both effects are caused by 
          time-dependent space charge in the bulk of these soft oxides 
          associated with slowly transporting and/or metastably trapped 
          holes (e. g., in E(delta)' centers). On the basis of this model, 
          bipolar transistors and screen-oxide capacitors were irradiated 
          at 60 degrees C at 200 rad(SiO2)/s in a successful effort to 
          match low-rate damage. These surprising results provide insight 
          into enhanced low-rate bipolar gain degradation and suggest 
          potentially promising new approaches to bipolar and BICMOS 
          hardness assurance for space applications.
      KP: OXIDE-SEMICONDUCTOR DEVICES, X-RAY, MOS DEVICES, 
          CO-60 IRRADIATIONS, RADIATION RESPONSE, BORDER TRAPS, CHARGE, 
          SIO2, TRANSISTORS, TEMPERATURE

(139) TI: THE CRRES SPACERAD HEAVY-ION MODEL OF THE ENVIRONMENT (CHIME) FOR 
          COSMIC-RAY AND SOLAR PARTICLE EFFECTS ON ELECTRONIC AND 
          BIOLOGICAL-SYSTEMS IN-SPACE
      AU: CHENETTE_DL, CHEN_J, CLAYTON_E, GUZIK_TG, WEFEL_JP, GARCIAMUNOZ_M, 
          LOPATE_C, PYLE_KR, RAY_KP, MULLEN_EG, HARDY_DA
      NA: LOCKHEED PALO ALTO RES LABS,PALO ALTO,CA,94304
          LOUISIANA STATE UNIV,BATON ROUGE,LA,70803
          UNIV CHICAGO,CHICAGO,IL,60637
          PHILLIPS LAB,BEDFORD,MA
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.2332-2339
      AB: We present a new time-dependent model of the interplanetary heavy 
          ion environment and a new set of software based on this model to 
          calculate energy deposit (LET) spectra and resulting single event 
          upset rates.
      KP: RATE PREDICTION, MODULATION, PROTON

(140) TI: TIME-DEPENDENCE OF SWITCHING OXIDE TRAPS
      AU: LELIS_AJ, OLDHAM_TR
      NA: USA,RES LAB,ADELPHI,MD,20783
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1835-1843
      AB: Metal-oxide semiconductor field-effect transistors (MOSFETs) were 
          irradiated and then annealed under alternating positive and 
          negative bias. The magnitude of the reversible trapped-oxide 
          charge component decayed over the course of several cycles (of 3 
          x 10(3) s each) in one of two processes studied. The HDL hole 
          trap model-is shown to explain these and other recent results.
      KP: SILICON DIOXIDE FILMS, RADIATION-INDUCED CHARGE, MOS DEVICES, 
          SEMICONDUCTOR CAPACITORS, INTERFACE TRAPS, POSITIVE CHARGE, 
          BORDER TRAPS, SIO2, GENERATION, CENTERS

(141) TI: MICROSCOPIC NATURE OF BORDER TRAPS IN MOS OXIDES
      AU: WARREN_WL, SHANEYFELT_MR, FLEETWOOD_DM, SCHWANK_JR, WINOKUR_PS, 
          DEVINE_RAB
      NA: SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM,87185
          FRANCE TELECOM,CTR NATL ETUD TELECOMMUN,F-38243 MEYLAN,FRANCE
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1817-1827
      AB: We show that enhanced hole-, electron-, interface-, and 
          border-trap generation in irradiated Si/SiO2/Si systems that have 
          received a high-temperature anneal during device fabrication is 
          related either directly, or indirectly, to the presence of 
          anneal-created oxygen vacancies. The high-temperature anneal 
          results are shown to be relevant to understanding defect creation 
          in zone-melt-recrystallized silicon on insulator materials. We 
          observe the electron paramagnetic resonance (EPR) of 
          trap-assisted hole transfer between two different oxygen 
          vacancy-type defects (E'(delta)-->E'(gamma) precursor) in hole 
          injected thermal SiO2 films. Upon annealing the hole injected 
          Si/SiO2 structures at room temperature, the E'(delta) center 
          transfers its hole to a previously neutral oxygen vacancy 
          (O-3=Si-Si=O-3) site forming an E'(gamma) center. This process, 
          also monitored electrically, shows a concomitant increase in the 
          border-trap density that mimics the growth kinetics of the 
          transfer-activated E'(gamma) centers. This suggests that both 
          effects are correlated and that some of the transfer-created 
          E'(gamma) centers are the entities responsible for the border 
          traps in these devices. One implication of these results is that 
          delayed defect growth processes can occur via slow trap-assisted 
          hole motion in SiO2.
      KP: INTERFACE-STATE GENERATION, SEMICONDUCTOR DEVICES, OXYGEN-VACANCY, 
          SI-SIO2 INTERFACE, SI/SIO2 INTERFACE, POSITIVE CHARGE, 
          SILICON DIOXIDE, BURIED SIO2, HOLE TRAPS, E' CENTERS

(142) TI: EVIDENCE FOR 2 TYPES OF RADIATION-INDUCED TRAPPED POSITIVE CHARGE
      AU: FREITAG_RK, BROWN_DB, DOZIER_CM
      NA: USN,RES LAB,WASHINGTON,DC,20375
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1828-1834
      AB: New experimental evidence is presented that supports a model that 
          assumes two distinguishable types of positive oxide charge 
          following, x-irradiation. Two new experiments have been performed 
          designed to separate the annealing properties of the two types of 
          trapped positive charge. It is found that one type of trapped 
          positive charge can be permanently removed at room temperature 
          using substrate hot electron injection. The second type of 
          trapped positive charge is found to be stable at temperatures up 
          to 160 degrees C
      KP: OXIDE-SEMICONDUCTOR CAPACITORS, GENERATION, DEVICES

(143) TI: SUMMARY OF THE 1994 IEEE INTERNATIONAL NUCLEAR AND SPACE 
          RADIATION EFFECTS CONFERENCE
      AU: OLDMAN_TR, FLEETWOOD_DM, CHEEK_T, MASSENGILL_L, VANVONNO_N, 
          SHANEYFELT_MR, EISEN_H, BOESCH_HE, SCHRIMPF_RD, CAMPBELL_A, 
          BENDEKOVIC_J, EMILY_D, GRAWET_S, MARSHALL_P, BUCHNER_S, GASIOT_J, 
          COSS_J, KRULL_W, FARREN_J, FREDERICKSON_R, LELIS_A, AMRAM_A, 
          LENAHAN_P
      NA: USA,RES LAB,WASHINGTON,DC
          SANDIA NATL LABS,LIVERMORE,CA,94550
          TEXAS INSTRUMENTS INC,DALLAS,TX,75265
          VANDERBILT UNIV,NASHVILLE,TN,37240
          HARRIS SEMICOND INC,MELBOURNE,FL,32901
          UNIV ARIZONA,TUCSON,AZ,85721
          USN,RES LAB,WASHINGTON,DC,20375
          UNIV MONTPELLIER 2,F-34095 MONTPELLIER,FRANCE
          JET PROPULS LAB,PASADENA,CA
          IBIS TECHNOL CORP,DANVERS,MA
          UKAEA,HARWELL INSTRUMENTS,HARWELL,BERKS,ENGLAND
          AEROSP CORP,LOS ANGELES,CA,90009
          PENN STATE UNIV,UNIVERSITY PK,PA,16802
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1804-1807
      DT: Editorial

(144) TI: SUMMARY OF THE 1994 IEEE INTERNATIONAL NUCLEAR AND SPACE 
          RADIATION EFFECTS CONFERENCE - COMMENTS
      AU: BOESCH_E
      NA: USA,RES LAB,WASHINGTON,DC
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          p.1810
      DT: Editorial

(145) TI: INTERFACE DEFECT FORMATION IN MOSFETS BY ATOMIC-HYDROGEN EXPOSURE
      AU: STAHLBUSH_RE, CARTIER_E
      NA: USN,RES LAB,WASHINGTON,DC,20375
          IBM CORP,THOMAS J WATSON RES CTR,YORKTOWN HTS,NY,10598
      JN: IEEE TRANSACTIONS ON NUCLEAR SCIENCE 1994 Vol.41 No.6 Pt1 
          pp.1844-1853
      AB: The formation of interface defects that occurs when atomic 
          hydrogen, H degrees, is introduced into the gate oxide of MOSFETs 
          at room temperature has been studied. MOSFETs with the edges of 
          the gate oxide at the source and drain exposed to the ambient 
          were placed downstream of a hydrogen plasma. Baffles prevent UV 
          light from the plasma from reaching the device. The effective 
          channel lengths ranged from 0.9 to 5 mu m. For comparison, bare 
          thermal oxides were exposed at the same time. The interface state 
          density in the MOSFETs was measured by charge pumping and in the 
          bare oxide by high-low capacitance-voltage measured with a Hg 
          probe. We observe that the induced damage has the same energy 
          distribution of interface traps in both types of samples. This 
          distribution is very similar to that produced by irradiation or 
          hot electron stressing. It is characterized by a broad peak at 
          0.7 eV above the valence band. A charge pumping analysis has been 
          developed to measure interface states as a function of position 
          above the MOSFET source and drain regions. The degradation 
          decreases exponentially from the point of H degrees entry at the 
          gate edges near the source and drain. This demonstrates that the 
          hydrogen enters the gate oxide of the MOSFET at the channel 
          edges. Furthermore, the decay length is constant within the 
          experimental uncertainty over three orders of magnitude of H 
          degrees dose and two orders of magnitude of interface trap 
          density. The exponential decrease of defect generation with 
          increasing lateral diffusion distance is in contrast to the 
          weaker oxide thickness dependence of the defect generation rate 
          observed by Cartier et al.[J. Non-Cryst. Sol., in press]. These 
          results indicate that defects such as Si-H bonds at the Si/SiO2, 
          interfaces act as catalysts for H-2 formation by reactions such 
          as Si- + H degrees --> SiH, SiH + H degrees --> Si- + H-2. 
          Furthermore, the number of these sites is not changed by the H 
          degrees exposure.
      KP: SI/SIO2 INTERFACE, SILICON, ELECTRONS

*** End of data ***