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Electrical performance and defect characterization of vertical GaN P-i-N diodes before and after irradiation with 2.5 MeV protons and neutrons is investigated. Devices exhibit increase in specific on-resistance following irradiation with protons and neutrons, indicating displacement damage introduces defects into the p-GaN and n^- drift regions of the device that impact on-state device performance. The breakdown voltage of these devices, initially above 1700 V, is observed to decrease only slightly for particle fluence < 10^13 ~\cm^ - 2. The unipolar figure of merit for power devices indicates that while the on-resistance and breakdown voltage degrade with irradiation, vertical GaN P-i-Ns remain superior to the performance of the best available, unirradiated silicon devices and on-par with unirradiated modern SiC-based power devices. [ABSTRACT FROM PUBLISHER]

Based on 3DG110 transistors and special gated NPN (GNPN) transistors, the characteristic of the synergistic effect between ionization and displacement defects induced by 40-MeV silicon (Si) ions with low fluence was investigated in terms of deep-level transient spectroscopy (DLTS). Nonlinear relationship, produced by the synergistic effect, between low fluence and radiation response can be obviously observed in the bipolar junction transistors (BJTs) under the exposure of 40-MeV Si ions. The DLTS signals of displacement defect centers and oxide-trapped charges are detected in the base–collector junction of the 3DG110 transistors. Meanwhile, based on the GNPN transistors, the DLTS signals of interface traps and displacement defects are measured in the base–collector junction. By comparison of the change in electrical parameters and the DLTS signals, it is found that the interface traps induce an enhanced effect to displacement defects in the base–collector junction of NPN BJT, whereas the oxide-trapped charge can suppress the DLTS signals of deep-level centers to a certain extent. Compared with the suppression action, the enhanced effect rising from ionization damage gives more contribution to the displacement damage. Moreover, the bias used during DLTS measurements can influence the characteristics of DLTS signals caused by oxide-trapped charge and interface traps. With increasing bias, both the height and temperature of ionization defect peaks in the DLTS spectra will increase, illustrating that concentration and energy level of these defects are raised. [ABSTRACT FROM PUBLISHER]

The feasibility to emulate fusion neutron irradiation, especially for the first wall of fusion reactors, by ion irradiation is studied. It is found that heavy ions with energies up to 300 MeV cannot produce weighted primary recoil spectra W p ( T ) similar to those of 14 MeV neutrons in SiC. On the contrary, the weighted secondary recoil spectra W s ( T ) of 14 MeV neutrons lie within the domain among the W p ( T ) of 1, 5, 10 MeV Si and C ions in SiC, and match well with the W p ( T ) at the Bragg peak region of mixed ion irradiation with 30% 10 MeV Si and 70% 4.8 MeV C ions in SiC, which indicates that ion irradiation with several MeV is sufficient to produce damaged regions along its track with damage distribution similar to that among the damaged regions produced by secondary recoils along the track of primary recoils in the case of 14 MeV neutron irradiation. The results suggest that it is possible to emulate the fusion neutron irradiation with low energy heavy ions on the order of few MeV. [ABSTRACT FROM AUTHOR]

The paper reports the 65 nm CMOS transistors exposed to 3 MeV protons to study the total ionizing dose (TID) effect and displacement damage (DD). The proton fluence of 7×10 14 p/cm 2 is equivalent to 9.5 MGy(SiO 2 ) total dose and 7.7×10 15 n/cm 2 1 MeV neutron equivalent fluence. Under this unprecedented hostile environment, we observed that the degradation of 65 nm CMOS transistors was mainly due to TID effect. Additional results from 10 keV X-ray irradiation implied no visible DD-induced degradation could be observed even for this extremely high proton fluence. [ABSTRACT FROM AUTHOR]

Metallic multilayer nanocomposites are known to have excellent interface self-healing performance when it comes to repairing irradiation damages, thus showing promise as structural materials for advanced nuclear power systems. The present study investigated the neutron irradiation displacement damage rate, spectra of the primary knocked-on atoms (PKAs) produced in the cascade collision, and the H/He ratio in four kinds of metallic multilayer nanocomposites (Cu/Nb, Ag/V, Fe/W, and Ti/Ta) versus neutrons’ energy. Results suggest that the three neutron induced damage effects in all multilayer systems increased with the increasing of incident neutrons’ energy. For fission reactor environment (1 MeV), multilayer’s displacement damage rate is 5–10 × 10 22 dpa/(n/cm 2 ) and the mean PKAs energy is about 16 keV, without any noteworthy H/He produced. Fe/W multilayer seems very suitable among these four systems. For fusion reactor environment (14 MeV), the dominant damage effect varies in different multilayer systems. Fe/W multilayer has the lowest displacement damage under the same neutron flux but its gaseous transmutation production is the highest. Considering the displacement damage and transmutation, the irradiation resistance of Ag/V and Ti/Ta systems seems much greater than those of the other two. [ABSTRACT FROM AUTHOR]

MRED is a Python-language scriptable computer application that simulates radiation transport. It is the computational engine for the on-line tool CRÈME-MC. MRED is based on c++ code from Geant4 with additional Fortran components to simulate electron transport and nuclear reactions with high precision. We provide a detailed description of the structure of MRED and the implementation of the simulation of physical processes used to simulate radiation effects in electronic devices and circuits. Extensive discussion and references are provided that illustrate the validation of models used to implement specific simulations of relevant physical processes. Several applications of MRED are summarized that demonstrate its ability to predict and describe basic physical phenomena associated with irradiation of electronic circuits and devices. These include effects from single particle radiation (including both direct ionization and indirect ionization effects), dose enhancement effects, and displacement damage effects. MRED simulations have also helped to identify new single event upset mechanisms not previously observed by experiment, but since confirmed, including upsets due to muons and energetic electrons. [ABSTRACT FROM AUTHOR]

The photoluminescence lifetime and spectrum of YBO 3 :Ce 3+ are observed before and after proton bombardment. The optical properties change under irradiation, and thus the material can record information about the radiation exposure. As the fluence of 1 MeV protons increases beyond 10 14 proton/cm 2 , the lifetime of YBO 3 :Ce 3+ decreases nearly exponentially. Furthermore, by changing the concentration of cerium, the sensitivity of the material to the radiation induced defects is controllable such that lower-doped YBO 3 :Ce 3+ is more sensitive to damage. [ABSTRACT FROM AUTHOR]

Based on 2N2222 NPN bipolar junction transistors (BJTs), synergistic effect between ionization and displacement defects induced by 3 MeV, 5 MeV and 10 MeV protons were researched. High-energy protons can be incident upon the silicon (Si) BJTs, producing displacement defects in silicon bulk and ionization damage in the oxide layer of BJTs, respectively. Both ionization and displacement damage result in the degradation of current gain of BJTs. At a given displacement dose, 10 MeV protons induce the maximum degradation of current gain of 2N2222 NPN BJTs, while 3 MeV protons cause the minimum degradation. In this case, non-ionizing energy loss (NIEL) methodology is not suitable to normalize the displacement damage induced by 3 MeV, 5 MeV and 10 MeV protons, which is attributed to the synergistic effect of ionization and displacement damage. The displacement defect centers in based-collector junction of 2N2222 transistor induced by 3 MeV, 5 MeV and 10 MeV proton exposures, were discovered and characterized by deep level transient spectroscopy (DLTS). Based on the comparison between the electrical parameters and the DLTS results, it is shown that, interface traps due to ionization damage induced by high-energy protons spread the emitter-base depletion layer, leading to the enhancement effects to displacement damage in the base-collector junction of NPN BJT. Meanwhile, bias voltage used during DLTS measurement influence characteristics of DLTS signals. With the increasing reverse bias, the value of \Delta C/C for VO, V_2(= / -), E4 and V2(- /0) + E5 centers increases. [ABSTRACT FROM PUBLISHER]

The properties of the combined effect between ionization and displacement defects have been researched on the base-collector junctions of 3DG110 silicon NPN bipolar junction transistors (BJTs) irradiated by 6 MeV carbon (C) ions with different fluence. The Gummel curve is used to characterize the degradation of the current gain at a given fluence. Nonlinear relationship, induced by 6 MeV C ions with lower fluence, between irradiation fluence and BJT radiation response can be observed, which is attributed to the combined effect. Evolution of deep level centers is characterized by the deep level transient spectroscopy (DLTS) with various biases. An unusual discovery is that the deep level centers decrease in the amplitude of DLTS peaks with increasing the biases. Based on the results of DLTS measurement, interface traps caused by 6 MeV C ions produce apparent enhanced effect to displacement defects in the base-collector junction of NPN BJT. Meanwhile, two factors, including bias used in DLTS measurement and irradiation fluence, can influence characteristics of DLTS signals caused by oxide-trapped charge. With increasing the bias or the irradiation fluence, both the height and the temperature of the defect peaks induced by the oxide charge in DLTS spectra will increase, illustrating concentration and energy level of the defects are enhanced. [ABSTRACT FROM PUBLISHER]

The combined effect of dual ion beam irradiated yttria-stabilized zirconia was investigated through Rutherford backscattering spectrometry/channeling (RBS/C), high resolution X-ray diffraction (HRXRD), atomic force microscopy (AFM) and transmission electron microscopy (TEM). Compared with other experimental results of single ion beam irradiation, a multistep damage accumulation model can also explain the irradiation effects of dual ion beam. Irradiation damage created by Ar + He ions are simply additive and no synergy effect has been observed. The variation trends of step height and displacement damage are similar. The synergic effects of displacement damage between heavy recoil atoms and α-particle in nuclear waste matrices will not cause more serious damage than the sum of two kinds of ions. The two experimental damage peaks are consistent with those calculated using stopping and range of ions in matter (SRIM). Phase stability and irradiation resistance is further confirmed by high resolution transmission electron microscopy (HRTEM). [ABSTRACT FROM AUTHOR]

The locations of conductive regions in TaOx memristors are spatially mapped using a microbeam and Nanoimplanter by rastering an ion beam across each device while monitoring its resistance. Microbeam irradiation with 800 keV Si ions revealed multiple sensitive regions along the edges of the bottom electrode. The rest of the active device area was found to be insensitive to the ion beam. Nanoimplanter irradiation with 200 keV Si ions demonstrated the ability to more accurately map the size of a sensitive area with a beam spot size of 40 nm by 40 nm. Isolated single spot sensitive regions and a larger sensitive region that extends approximately 300 nm were observed. [ABSTRACT FROM PUBLISHER]

The synergistic effect between displacement damage dose (DDD) and analog transient radiation effects on electronics (ATREE) in an operational amplifier (LM124) (opamp) from three different manufacturers is investigated. Pulsed X-ray experiments have highlighted ATREE sensitivity on devices significantly more important following exposure to fission neutrons than for unirradiated devices. A previously developed simulation tool is used to model ATREE responses taking into account the electrical parameters degradation due to displacement damage phenomenon. A good agreement is observed between model outputs and experimental ATREE results. [ABSTRACT FROM PUBLISHER]

A system to monitor the radiation levels is required in the Large Hadron Collider (LHC) and its injection lines in order to quantify the radiation effects on electronics. Thus, the RadMons were installed in critical areas where equipment is or will be placed. The first years of operation, successive test campaigns and new requirements, raised the need for a new design of the monitor. The architecture of the new RadMon, the radiation reliability and the design strategy adopted for the sensors, used for monitoring the mixed radiation field of the LHC accelerator, are described highlighting the achieved improvements in terms of radiation robustness and measurement accuracy of a device which is of interest for many other research institutes. [ABSTRACT FROM PUBLISHER]

Effects of bias conditions on 10 MeV Br ion irradiation were investigated in NPN SiGe HBTs. Pre- and post-radiation direct current (DC) characteristics, such as current gain, leakage current, Early voltage and neutral base recombination, were studied and used to quantify the dose tolerance to 10 MeV Br ion. Experiment results for different bias conditions were compared and discussed in detail. It is found that performance degradations are indeed bias dependent. The BE junction reversed-biased mode suffers the largest degradation and the case with BE junction forward-biased shows the smallest degradation. The underlying physical mechanisms are analyzed and investigated in present work. The injection annealing effect of displacement damage is found to be responsible for the different irradiation response of SiGe HBTs under three bias conditions. [ABSTRACT FROM AUTHOR]

This study explores the degradation of silicon-based bipolar junction transistors (BJTs) exposed to a californium-252 source. Both n–p–n and p–n–p BJTs received neutron irradiation of different fluxes (6.3 × 104 cm −2 s−1 to 1.5 × 106 cm −2 s−1). The proportion of the change of reciprocal current gain to neutron fluence increases with the decrease of neutron flux, implying that devices exposed to irradiation of lower neutron flux will suffer severer radiation damage if the total neutron fluence is kept constant. Results obtained by eliminating the impact of accompanying gamma irradiation and the impact of different neutron energy spectra from the degradation of BJTs confirmed this conclusion for both types of BJTs. A kinetic model based on the theory of diffusion-limited reactions was used to analyze the microscopic mechanism, and its results agreed with the experimental results. The simulation results also indicate that lower neutron flux favors the formation of stable defects and reduces the recombination of vacancies and interstitials. This work demonstrates that neutron flux effect also exists in silicon-based BJTs exposed to a californium-252 source and it is related to the defect evolution process in irradiated materials. [ABSTRACT FROM AUTHOR]

In this study, the ionizing radiation (gamma-irradiation) response of the metal-ferroelectric-semiconductor (MFS) type capacitors whose interfacial layer is bismuth titanate (Bi 4 Ti 3 O 12), which is from the Aurivillius family, was investigated. The capacitance-voltage (C V) and conductance-voltage (G / ω-V) characteristics and the device parameters derived from these characteristics provide essential information about the radiation response. Therefore, MFS-type capacitors in which their Schottky/rectifier contacts Au and interfacial layer Bi 4 Ti 3 O 12 (BTO) were prepared and exposed to various doses of gamma-rays. The voltage-dependent C and G / ω data were obtained before irradiation and after some irradiation doses using the Hewlett Packard Impedance Analyzer. Experimental results showed that the C V curves exhibited multilayer capacitor behavior before and after radiation rather than conventional Schottky structures due to the very thin Silicon dioxide (SiO 2) interlayer at the BTO/Si interface, which was assumed to form during the annealing of BTO films in air ambient. On the other hand, the C-G / ω-V curves exhibited asymmetric and hysteretic behavior because of the different electrical properties at the bottom and top interfaces and the natural ferroelectric behavior of the BTO. On the other hand, considering the radiation effects, the C-G/ω-V characteristics and other device parameters did not show any significant changes at the 5 kGy irradiation dose, but significant differences were observed in all parameters at the 22 kGy dose. Therefore, it can be concluded that these MFS-type structures with the BTO interlayer can be used as a capacitor or radiation sensor at doses around 5 kGy and below 22 kGy. However, it is not recommended to use them as capacitors at doses close to 22 kGy due to the large capacitive change (approximately tenfold decrease) at this dose. Besides, the tendency of the device to deteriorate at 22 kGy doses indicates that it is not suitable for use as a capacitor or radiation sensor above 22 kGy gamma-irradiation doses. • In this study, the bismuth titanate-based metal-ferroelectric-semiconductor (MFS) type capacitor was produced and the effects of gamma-irradiation on the device were investigated. • The device exhibited multilayer capacitor behavior before and after irradiation due to the naturally occurring SiO 2 interlayer at Si/BTO interface. • The device showed a tendency to deteriorate at 22 kGy ionizing radiation doses, but no significant change was observed in device parameters at 5 kGy doses. • This MFS-type structure can be used as a capacitor or radiation sensor at doses around 5 kGy and below 22 kGy. • It is not recommended to use this device in ionizing radiation environments at doses above 22 kGy. [ABSTRACT FROM AUTHOR]

In order to assess the space compatibility of GaN-HEMT technology, radiation hardness tests are an essential requirement. In this field, Gallium Nitride exhibits excellent robustness with respect to radiation and GaN-based devices are providing very promising results for most of the typical space configurations. Nevertheless, in presence of very high fluence levels, displacement damage takes place reducing the device performances from the static to the dynamic point of view. This paper shows how the combination of radiation hardness tests and the improvement of deep level analysis allows us to quantify the DC and pulsed performance decrease induced by proton irradiation on a technology designed for space applications, highlighting some signatures useful for an early detection of the displacement damage. Results provide a consistent demonstration of (i) threshold voltage positive shift and (ii) trapping effect enhancement correlated with the proton irradiation fluences. [ABSTRACT FROM AUTHOR]

Proposed fusion and advanced (Generation IV) fission energy systems require high-performance materials capable of satisfactory operation up to neutron damage levels approaching 200 atomic displacements per atom with large amounts of transmutant hydrogen and helium isotopes. After a brief overview of fusion reactor concepts and radiation effects phenomena in structural and functional (nonstructural) materials, three fundamental options for designing radiation resistance are outlined: Utilize matrix phases with inherent radiation tolerance, select materials in which vacancies are immobile at the design operating temperatures, or engineer materials with high sink densities for point defect recombination. Environmental and safety considerations impose several additional restrictions on potential materials systems, but reduced-activation ferritic/martensitic steels (including thermomechanically treated and oxide dispersion-strengthened options) and silicon carbide ceramic composites emerge as robust structural materials options. Materials modeling (including computational thermodynamics) and advanced manufacturing methods are poised to exert a major impact in the next ten years. [ABSTRACT FROM AUTHOR]

Displacement damage doses measured by the ICARE-NG/OSL sensor on board the French JASON2 spacecraft from CNES, the French space agency, are compared to predictions performed with (1) proton measurements performed with the spectrometers on board the same spacecraft/instrument and (2) protons spectrum predicted by the legacy AP8 min model and the future AP9 perturbed model. [ABSTRACT FROM PUBLISHER]

Abstract: This study investigates whether particle irradiation of yttrium borate doped with cerium(III) (YBO3:1%Ce3+) and yttrium borate doped with europium(III) (YBO3:6%Eu3+) can cause displacement damage and whether photoluminescent emission changes with the radiation dose. Although phosphors scintillate upon irradiation, of more interest in this study are the permanent changes caused by non-ionizing energy absorption, which alters the environment of the luminescent centers and thus the luminescence. Photoluminescence spectroscopy indicates that the emission intensity of both YBO3:1%Ce3+ and YBO3:6%Eu3+ decreases with increasing proton fluence. The sensitivity of changes in the emission intensity to proton fluence is 5 times more in the europium-doped samples than in the cerium-doped samples. [Copyright &y& Elsevier]

The effects of radiation on memristors created using tantalum oxide and titanium oxide are compared. Both technologies show changes in resistance when exposed to 800 keV Ta ion irradiation at fluences above 10^10~\cm^\-2. TaOx memristors show a gradual reduction in resistance at high fluences whereas TiO_2 memristors show gradual increases in resistance with inconsistent decreases. After irradiation TaOx devices remain fully functional and can even recover resistance with repeated switching. TiO_2 devices are more variable and exhibit significant increases and decreases in resistance when switching after irradiation. Irradiation with 28 MeV Si ions causes both technologies to switch from the off-state to the on-state when ionizing doses on the order of 60 Mrad(Si) or greater (as calculated by SRIM) are reached without applying current or voltage to the part. Irradiation with 10 keV X-rays up to doses of 18 Mrad(Si) in a single step show little effect on either technology. TaOx and TiO_2 memristors both show high tolerance for displacement damage and ionization damage and are promising candidates for future radiation-hardened non-volatile memory applications. [ABSTRACT FROM PUBLISHER]

Measurements of single particle displacement damage are presented as discrete increases in reverse-biased diode leakage current, or current steps, caused by individual heavy ions in ^252Cf-irradiated JFET diodes. The maximum size of measured current steps agrees with calculations obtained from the expression for Shockley-Read-Hall generation when the radiation-induced defect density is derived from Monte Carlo simulations of atomic displacements and the electric field enhancement of defect emission is taken into account. The distribution of the current steps shows good agreement with experimental data. [ABSTRACT FROM PUBLISHER]

The dependence of displacement damage effects in silicon charge coupled devices on the bias conditions during proton irradiation has been assessed. The devices have been fully characterized for dark signal increase, charge transfer degradation and the generation of random telegraph signals. A 5 to 10% higher degradation rate for all these parameters has been seen when unbiased during irradiation, under conditions typically used for a proton irradiation campaign, compared with the case when operating the devices during the irradiation. Room temperature annealing has been investigated and shows a bias dependence for all parameters tested. A reverse annealing behavior of bulk dark signal and random telegraph signals following illumination is reported for the first time. Both the annealing and reverse annealing observations may, in part, be attributed to the behavior of the trivacancy. [ABSTRACT FROM PUBLISHER]

Abstract: Silicon–germanium (SiGe) heterojunction bipolar transistors (HBTs) were exposed to 25MeV Si4+ ion with equivalent absorbed dose from 200krad(Si) to 10Mrad(Si). The transistor characteristics such as forward Gummel, reverse Gummel, leakage current of base–emitter (BE) junction and base–collector (BC) junction were studied before and after irradiation and were used to quantify the dose tolerance to the swift heavy ion irradiation. The base current was found more sensitive than collector current and current gain appeared to decline with the ion fluence increasing. On the reverse Gummel characteristics, besides the degradation in the base current, an unexpected increase in emitter current was observed with the ion fluence increasing. The output characteristics of the irradiated SiGe HBTs exhibited a decrease in the collector current with the increasing ion fluence. The reverse leakage current of BE and BC junctions increased with the increase in ion fluence. The self-annealing effect at room temperature was found less influence on the performance degradation. The displacement damages in the transistor were found to dominate the performance degradation of SiGe HBT after 25MeV Si4+ ion irradiation. [Copyright &y& Elsevier]

More than 400 radiation monitoring devices are nowadays installed in the CERN LHC tunnel and its adjacent shielded areas to measure radiation effects on the electronics and anticipate possible device degradation. Supported by the experience accumulated in the last years' operation, a major system upgrade has been prepared. In this paper, the operational architecture of the new detector will be discussed focusing mainly on the advantages provided to the accelerator radiation monitoring impacting electronics installed in its vicinity. The new data acquisition software infrastructure will be detailed referring to the implemented approach to make the management and the maintenance of the entire system easier. [ABSTRACT FROM AUTHOR]

Three-dimensional TCAD simulations are used for physics-based prediction of space radiation effects in III-V solar cells, and compared with experimentally measured characteristics of a p^+ n GaAs solar cell with AlGaAs window. Dark and illuminated I-V curves as well as corresponding performance parameters are computed and compared with experimental data for 2 MeV proton irradiation at various fluences. We analyze the role of majority and minority carrier traps in the solar cell performance degradation. The traps/defects parameters used in the simulations, for n-type and p-type GaAs, are derived from Deep Level Transient Spectroscopy (DLTS) data. The physics-based models allow a good match between simulation results and experimental data. However, assuming the device performance is dominated by a single recombination center is not adequate to completely capture the degradation mechanisms controlling the photovoltaic performance. [ABSTRACT FROM AUTHOR]

The degradation of optical power for superluminescent diodes is in situ measured under exposures of protons with various energies (170 keV, 3 MeV and 5 MeV), and 25 MeV carbon ions for several irradiation fluences. Experimental results show that the optical power of the SLDs decreases with increasing fluence. The protons with lower energies cause more degradation in the optical power of SLDs than those with higher energies at a given fluence. Compared to the proton irradiation with various energies, the 25 MeV carbon ions induce more severe degradation to the optical power. To characterize the radiation damage of the SLDs, the displacement doses as a function of chip depth in the SLDs are calculated by SRIM code for the protons and carbon ions. Based on the irradiation testing and calculation results, an approach is given to normalize the equivalence of displacement damage induced by various charged particles in SLDs. [ABSTRACT FROM AUTHOR]

Abstract: Ion Beam Induced Charge (IBIC) and Deep Level Transient Spectroscopy (DLTS) were used to investigate displacement damage caused by MeV energy ion beams in Si diodes. The devices were irradiated with 3MeV Si ions to create displacement damage and a 2MeV He ion beam was used for IBIC. The IBIC signal deterioration was measured as the function of the ion fluence and DLTS was used to identify the defects and their quantities. We used a new calculation method based on previous work by Fizzotti et al. [9] and more recently by Vittone [10] to determine the fraction of the active traps that affect the lifetime. The first application of this method is presented in this paper. [Copyright &y& Elsevier]

A review of radiation-induced displacement damage effects in semiconductor devices is presented, with emphasis placed on silicon technology. The history of displacement damage studies is summarized, and damage production mechanisms are discussed. Properties of defect clusters and isolated defects are addressed. Displacement damage effects in materials and devices are considered, including effects produced in silicon particle detectors, visible imaging arrays, and solar cells. Additional topics examined include NIEL scaling, carrier concentration changes, random telegraph signals, radiation hardness assurance, and simulation methods for displacement damage. Areas needing further study are noted. [ABSTRACT FROM PUBLISHER]

The fifty year history of radiation effects in bipolar transistors at NSREC is summarized, covering neutron-induced displacement damage, total ionizing dose response (including enhanced low dose rate sensitivity, ELDRS) and single event effects. These phenomena, particularly TID and ELDRS in bipolar transistors, have received significant attention at NSREC. Several other radiation effects such as thermal mechanical shock, electrical overstress, prompt dose rate photoresponse and the response to neutral particle beams are not addressed. [ABSTRACT FROM PUBLISHER]

TiO2 memristor devices may be a promising candidate for radiation hardened next-generation memories. They have been shown to be tolerant to both gamma radiation and alpha particles. In this work, we expand on the radiation studies previously done and measure the response of a large number of TiO2 memristor test devices to both neutrons and protons. We also use simulations to estimate the amount of damage done for each type and level of radiation and correlate the number of displacements to the experimentally measured current-voltage characteristics of the devices. We show that the TiO2 thin films are tolerant to high fluences of both neutrons and protons. [ABSTRACT FROM PUBLISHER]

The total-dose-effects of gamma and proton irradiations on high-voltage silicon–germanium heterojunction bipolar transistors with the collector electrode elicited from the backside of the substrate are investigated. Pre- and post-radiation DC characteristics of the transistors are used to quantify the dose tolerance to the two different irradiation sources. Measurement results indicate that the devices exhibit a total dose tolerance up to Mrad level. The device response is indeed radiation source dependent and the proton irradiation can produce a more significant damage than the gamma irradiation, causing more pronounced performance degradation. The experimental results from both irradiations are compared and discussed in detail, and furthermore the underlying physical mechanisms are analyzed and investigated. The considerably different degradation behaviors are attributed to the extra displacement damage besides ionizing damage induced by the proton irradiation. [ABSTRACT FROM AUTHOR]

We present the results of a radiation damage experiment on Alx\rm Ga1-{\rm x}{\rm N/GaN} high electron mobility transistors. The basic mechanism underlying the observed high radiation tolerance appears to be a strong internal piezoelectric field near the two-dimensional electron gas that causes scattered carriers to be reinjected. [ABSTRACT FROM AUTHOR]