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In order to promotion the RF performance, a grade In1-xGaxAs channel (G-HEMT) introduced to the AlGaAs/InGaAs HEMT. The G-HEMT with the grade In1-xGaxAs channel forms a deeper potential well and confines more electrons in the channel, results in improving the DC and RF characteristics. Moreover, because of the grade In1-xGaxAs is effectively reduced the peak electric field, and leads to a significant increase in breakdown voltage (BV). Moreover, the G-HEMT also increases resistance to single event effects (SEE). The simulation results indicate that the fmax is significantly increased to 889 GHz of G-HEMT from 616 GHz of conventional AlGaAs/InGaAs HEMT (C-HEMT). The the fT is significantly increased to 521 GHz of G-HEMT from 326 GHz of C-HEMT, as well as the IDsat is increased by 64.8% and the BV increases by 37%. In addition, the SEE peak drain current of G-HEMT is dramatically reduced 51%. [ABSTRACT FROM AUTHOR]

The space environment is a very harsh operating environment, and space radiation can directly affect the operation of electronic devices causing total ionizing dose (TID), single event effect (SEE) and displacement damage (DD). For most devices TID and SEE are the two most dominant effects, the study of TID and SEE mechanism is one of the main tasks in modern spacecraft design. Previous studies show that there is a synergistic effect between TID and SEE. The TID will significantly affect the sensitivity of the SEE, and the effect rules and mechanisms are not consistent due to the different device process sizes and processes. There are few reports about the synergistic effect of SOI SRAM devices in the world, and the research on SOI SRAM with special memory cell structure has not been carried out. To further elucidate the synergistic effect between TID and SEE in SOI SRAM, an experimental study was conducted using a domestic 130 nm 7T SOI SRAM. The TID and SEE experiments were carried out at the China Institute of Atomic Energy TID test platform and HI-13 tandem accelerator SEE test platform. Before the SEE experiment, three groups of SOI SRAMs were irradiated by total dose of 300, 500 and 750 krad, respectively, and finally the change of the single event upset (SEU) cross section of the SOI SRAM after different doses TID irradiation was obtained. The experimental result shows that the SEU cross section of the SOI SRAM decreases to 80.5%, 66% and 50.5% at three LET values of 13.85, 21.8, and 37.4 MeV·cm2/mg after TID irradiation. There is no obvious difference found in the SEU cross section under different writing modes, which means that the synergistic effect of these devices has no data-dependent. The saturation cross section of the device also shows a trend of decreasing with increasing dose, up to 19.5%, and no significant change in the SEU threshold was found in this study. By analyzing the SEU cross section of flip-flop type 1→0 flip-flop and 0→1 flip-flop, it is found that the delay efficiency of the delay transistor N5 is the main reason for the influence on the SEU cross section. After the mechanism analysis, it is concluded that the delay transistor N5 has an increased equivalent off-state resistance due to the decrease of carrier mobility caused by TID, and this phenomenon is the main reason for the decrease of SEU cross section. The anti-SEE performance of SOI SRAM with special mechanism will be enhanced gradually with longer in-orbit time, which provides new insight for future electronic devices radiation-hardend.

As the central control component in aerospace products, SRAM-based FPGA finds extensive application in space. In its operational context, the space radiation environment introduces single event effect (SEE) and space electrostatic discharge effect (SESD) in FPGAs. This paper investigates SEE and SESD in SRAM-based FPGA using an integrated simulation method that combines device-level and circuit-level analyses. The findings reveal that the distinction in signal transmission primarily lies in the number of upsets and their correlation with the initial state. SEE can lead to single-bit or multi-bit upsets in SRAM, while SESD typically induces multi-bit upsets (MBU) in SRAM. Furthermore, the logic upset caused by SEE exhibits almost no correlation with the initial state of SRAM. Conversely, the upset caused by SESD is linked to the initial state, and the threshold voltage of Single Event Upsets (SEU) in different initial states is not uniform. [ABSTRACT FROM AUTHOR]

With the rapid development of semiconductor technology, the reduction in device operating voltage and threshold voltage has made integrated circuits more susceptible to the effects of particle radiation. Moreover, as process sizes decrease, the impact of charge sharing effects becomes increasingly severe, with soft errors caused by single event effects becoming one of the main causes of circuit failures. Therefore, the study of sensitivity evaluation methods for integrated circuits is of great significance for promoting the optimization of integrated circuit design, improving single event effect experimental methods, and enhancing the irradiation reliability of integrated circuits. In this paper, we first established a device model for the charge sharing effect and simulated it under reasonable conditions. Based on the simulation results, we then built a neural network model to predict the charge amounts in primary and secondary devices. We also propose a comprehensive automated method for calculating soft errors in unit circuits and validated it through TCAD simulations, achieving an error margin of 2.8–4.3%. This demonstrated the accuracy and effectiveness of the method we propose. [ABSTRACT FROM AUTHOR]

Copyright of Journal of National University of Defense Technology / Guofang Keji Daxue Xuebao is the property of NUDT Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the widespread application of nano integrated circuits in high radiation environments such as aerospace and military, single event effects have become the main factor affecting their stability and reliability. To enhance the radiation resistance of circuits, a hardened latch design method based on Schmitt triggers is proposed. This method integrates multiple circuit elements such as Schmitt triggers, transmission gates, C-element, and inverters, and verifies its SET shielding and anti SEU capabilities through HSPICE simulation. The results showed that the hardened latch successfully blocked 148ps positive SET pulse and 137 ps negative SET pulse, and quickly recovered after high-energy event bombardment. Compared to traditional latches, study designed latch exhibited significant advantages in area ( $34.23~\mu $ m2), delay (40.25 ps), power consumption (11.62 uw), and noise resistance, with an output signal-to-noise ratio close to 30 dB. The PVT fluctuation analysis shows that the latch has strong stability in power consumption, delay and hardness. The research provides new ideas for radiation hardened design of nano integrated circuits, which is of great significance for improving the reliability of electronic devices in high radiation environments.

As the core of high-voltage direct-current transmission technology, the DC converter valve and its key power device thyristor face a high risk of failure caused by atmospheric neutron when operating in high-altitude areas. The atmospheric neutron failure rate of thyristors used at high altitudes can be quantitatively evaluated by conducting accelerated irradiation tests. The accelerated irradiation experiments of 8.5 kV/5 kA thyristor for DC transmission were carried out at different temperatures by using the China spallation neutron source. The atmospheric neutron-induced single-event burnout (SEB) for thyristor was verified by experiments. It is manifested as a sudden surge in reverse bias leakage current during irradiation, and the device loses its high voltage blocking ability. The failure rates of thyristor caused by atmospheric neutrons were also evaluated based on the accelerated irradiation experimental results. The reverse bias voltages and junction temperatures of thyristor are the key factors affecting the failure rates. The atmospheric neutron-induced failure rates increase exponentially with the reverse bias voltage. The atmospheric neutron failure rate of the 8 500 V thyristor operating at 4 350 V will reach 673 FIT at room temperature at sea level; when the bias voltage drops to 4 100 V (a decrease of about 5.7%), the atmospheric neutron failure rate can be reduced to 11 FIT. In addition, the failure rate increases with the decrease of temperature. The failure rate at 5℃ is nearly 6 times higher than that at 25℃ when the device is biased at 50% of the rated voltage. Based on TCAD simulations, the failure mechanism of thyristor caused by irradiation is further verified. The simulation results show that the SEB failure is directly related to the avalanche breakdown effect-induced by the incident radiation particles. For radiation-induced SEB failure of thyristors, the sensitive region is the N-drift/P-substrate junction depletion region (corresponding to the electric field concentration region under reverse bias of thyristors). When radiation particles are incident into the sensitive region, it can cause the concentration of electric field near the incident location, resulting in additional electric field spikes. If the peak of the electric field exceeds the critical electric field Ec (about 1.64×105 V/cm), it will induce avalanche breakdown. The high voltage reverse bias high current state caused by avalanche breakdown ultimately leads to the failure of the thyristor. The avalanche breakdown effect is positively correlated with the reverse bias voltage of thyristor and negatively correlated with the junction temperature. This is consistent with the variation of atmospheric neutron failure rates with bias voltages and junction temperatures.

Deep space exploration, nuclear industry and high energy physics raise higher requirements for the radiation hardness of integrated circuits. However, the existing radiation hardening technologies, such as radiation hardness by design based on bulk silicon technology or silicon-on insulator (SOI) process, are difficult to ensure that the electronics in spacecrafts and nuclear facilities function well in extreme space and nuclear radiation environments. In response to the lack of clear technical paths for the development of ultra-high radiation-hardened chip, a new type of highly radiation-hardened technique was introduced in this paper, named configurable SOI (CSOI). This technology innovatively employs twice bonding and cutting method to fabricate ultra-high radiation hardened 200 mm wafers with embedded configurable silicon layers. The 0-18 μm CSOI complementary metal oxide semiconductor (CMOS) process was successfully developed, which opens up a new route to achieve radiation hardness through in-situ radiation compensation. After the fabrication of CSOI devices, the configuration layer voltage can be tuned flexibly to compensate for the performance degradation due to total ionizing dose (TID) effect and simultaneously suppress the parasitic transistor effect triggered by single event effects (SEE). This helps to improve the radiation hardness of the CSOI transistors. Technology computer aided design (TCAD) simulations validate the tuning mechanism of configurable layer that a negative bias does good to the hardness of both TID and SEE in N-type MOSFET. Based on the CSOI process platform, a design methodology for integrated circuits was developed through assessing the impact of tuning granularity (down to transistor level) and range (from -20 V to 5 V) of configurable layer on the performance and radiation tolerance of static random-access memory (SRAM) cell. Then, the optimized tuning strategy of configurable layer was determined, and a CSOI 4kb SRAM was designed and fabricated with high radiation tolerance. The TID irradiation of the CSOI 4kb SRAM chip was performed at the 60Co gamma irradiation source of Peking University and the SEE experiment was carried out at the Space Environment Simulation and Research Infrastructure (SESRI) in Harbin Institute of Technology. Radiation experiments confirm that the CSOI SRAM achieves up to a level of 6 Mrad(Si) for TID hardness and the threshold of single event upset is greater than 118 (MeV·cm2)/mg, which reaches world-class levels. It is expected to be applied in extreme fields such as deep space exploration and nuclear emergency.

The single event effect on SiC MOSFET was studied for space applications. 1 200 V SiC MOSFET from four manufactures was irradiated with heavy ions. The ions of carbon (C), germanium (Ge), tantalum (Ta), bismuth (Bi), and uranium (U) were used. The linear energy transfer (LET) of ions was 0.26-118 MeV·cm2/mg. The static drain-source bias voltage of 50-600 V was applied on the devices under test and the electrical characteristics were measured during irradiation. The post irradiation gate stress (PIGS) test was performed. The experiment results show that single event transient current (SETC) is induced by heavy ions at 50-100 V bias voltage, single event leakage current (SELC) is induced by heavy ions at 200 V bias voltage, and single event burnout is induced by heavy ions at 200-600 V bias voltage. The experiment results confirm that the gate oxide of SiC MOSFET is the most sensitive to single event effect. Biased at about 5% of the rated breakdown voltage, the latent gate oxide damage may be induced by heavy ions. The latent gate oxide damage may further degrade to lead the gate failure during PIGS test. The latent gate oxide damage is the function of incident ion LET and bias voltage, as well as ion fluence, which is a cumulative effect. Dependent on the severity of latent gate oxide damage, the gate stress time to trigger gate failure may exceed 300 s. The mechanism of accumulate charge damage was proposed. The electric field in the gate oxide layer increases due to charges generated by the incident ions at different locations. The accumulate damage of gate oxide is caused. It is necessary to evaluate the effect of latent gate oxide damage induced by heavy ions in SiC MOSFETs for single event effect test for space application, the ion fluence used should be calculated based on the orbit and mission period, and the appropriate gate stress time should be evaluated for PIGS test.

Neutron-induced single event effects have potential influence on the reliability of electronic devices in aircraft and ground-based nuclear facilities. The white neutron source, generated by heavy metal target bombardment from proton accelerators, is an important tool for studying these effects. Neutron irradiation experiments can provide valuable information such as cross section or threshold for neutron single event effects, allowing prediction of device failure rates in neutron irradiation environments and providing data to support electronic device radiation hardening. Protons from the CYCIAE-100, a 100 MeV proton cyclotron accelerator in China Institute of Atomic Energy, bombard a tungsten target and undergo a scattering reaction, producing white neutrons. Based on nuclear reaction theory and Monte Carlo method, the yield, spectrum, and angular distribution of neutrons produced from the interaction between 100 MeV protons and a tungsten target were simulated. The results show that each 100 MeV proton can produce 0.33 neutrons on average. The neutron energy range is 0-100 MeV, the neutron fluence initially rises and then declines as the energy increases, with the peak occurring near 1 MeV. The angular distribution of the neutrons along the direction of the proton beam is observed to be axisymmetric, and as the emission angle increases, the neutron fluence first decreases and then increases, with the lowest neutron fluence occurring at 90°. The neutron beam in the emission direction of 0° is selected to carry out the single event effect experiment. The energy spectrum of white neutrons is measured by the neutron time-of-flight method based on two liquid scintillation detectors. The neutron energy spectrum is obtained in the range of 3-100 MeV, and when the proton beam is 100 MeV/1 μA, the neutron flux is 3.3×104 cm-2·s-1 at the distance of 15 m from the W target, which meets the requirements of neutron single event effect experiments. Due to the fact that the neutron energy of CYCIAE-100 white neutron source is limited to a maximum of 100 MeV, a direct simulation of the atmospheric neutron energy spectrum is unattainable. Also, disparities exist between the energy spectrum of this neutron source and that of the neutron radiation environment in nuclear industry. Therefore, it is necessary to consider the single event effect response of the device under irradiation with different energies neutron and to explore the development of an accurate approach for experimental evaluation of neutron single event effects.

The rapid growth of China’s aerospace sector, along with the creation of expansive space configurations like space stations, and the integration of high-performance electric propulsion systems require power semiconductor devices of increasingly better performance. Consequently, it is vital to achieve a breakthrough in the research of radiation-resistant SiC high-voltage power devices. Various bias voltages were applied to SiC JFET devices and subsequent heavy-ion irradiation experiments were conducted. These experiments reveal the existence of two failure modes: single event leakage degradation and single event burnout (SEB), which are similar to those found in SiC MOSFET. However, due to the lack of an irradiation-sensitive gate oxide structure, the onset of leakage degradation is higher in SiC JFET than in SiC MOSFET. This implies that SiC JFET have a larger safe operating region. Single event leakage degradation is observed during heavy-ion irradiation when the drain bias voltage is set to 350 V. The extent of leakage degradation is directly proportional to the absolute value of the drain bias voltage and the quantity of heavy-ion fluence. Additionally, SEB is observed when the heavy-ion irradiation takes place at a drain bias voltage of 400 V. The Sentaurus TCAD simulation study shows that the single event effect can be divided into two phases. The first phase involves heavy-ion irradiation, which is followed by collisional ionisation along the incidence path, resulting in the generation of a large number of carriers. The electric field along the incidence path then produces a current from the drain to the gate. The drain bias voltage was set at 350 V, causing the P+ gate area and the PN end of the N- drift area to reach a temperature of 2 500 K due to the high-density current. It is possible that thermal stresses are responsible for the leakage degradation. The modulation of the electric field in the second stage leads to an increase in the electric field at the junction of the N+ substrate and the N- drift region, reaching up to 3.2 MV/m. This strong electric field persists for a significant period and results in substantial collision ionisation. As a consequence, the local temperature at the junction of the N+ substrate and N- drift region continues to rise to 3 000 K. Exceeding the sublimation temperature of SiC material results in SiC JFET device burnout. Adding a buffer layer at the junction of the N+ substrate and N- drift region may enhance the SEB threshold voltage of SiC JFET. This study guides radiation reinforcement of SiC JFET devices and supports the application of SiC power devices in space environments.

The advantages of SiC MOSFETs (metal-oxide semiconductor field effect transistor) make this technology attractive for space, avionics and high-energy accelerator applications. However, the current commercial technologies are still susceptible to single event effects (SEEs) and latent damages induced by the radiation environment. In commercial SiC MOSFETs exposed to heavy ions, two types of latent damages were experimentally observed. One type is observed at bias voltages just below the degradation onset voltage and involves the gate oxide. The other type of damage was observed at bias voltages below the single event burnout (SEB) limit and which was attributed to changes in the silicon carbide lattice. The key parameter of SiC MOSFET, JFET region width, has been considered as the main influence factor of SEEs of SiC MOSFET. Aiming at this influence factor, SEE experiment was carried out on 12 kV SiC MOSFET devices with different JFET region widths of the same structure to investigate the influence of different JFET region widths on the device’s SEEs burning threshold voltage, leakage degradation threshold voltage, and the device performance under negative gate voltage conditions, and the test results show that the leakage degradation threshold voltage increases with the decrease of the JFET region width. Reducing the JFET region width of the device can effectively improve the SEEs resistance of the device, this effect is also observed under negative gate voltage bias conditions. Under negative gate voltage bias conditions, the effect of JFET region width on the SEEs of the device is reduced by the negative gate voltage. Sentaurus TCAD is used for simulation, and the simulation results confirm that the JFET region width and the negative gate voltage bias affect the accumulation of holes in the JFET region under the oxide layer, which in turn affects the oxide layer field strength, and thus affects the single event leakage degradation of the device. It is also demonstrated that SEB is caused by a localized energy pulse due to ion collisional ionization, followed by avalanche multiplication, which generates a large amount of Joule heat and leads to permanent structural damage in the device. The whole burn-in process does not correlate well with the JFET region width, and all changes in the JFET region width do not have a significant effect on the burn-in voltage, which is in line with the experimental results. The JFET region width is only one of the factors affecting the single event leakage degradation effect. The in-depth research will be carried out, with the help of advanced TCAD software to find out the intrinsic mechanism causing this phenomenon, in order to provide technological support for the radiation hardening of SiC power devices.

There are a lot of particles in space, including protons and heavy ions mainly. These particles in space can induce different radiation effects on the electronic devices, such as single event effect and displacement damage. The single event effect is the main reason of the abnormal function in spacecraft. Astronautical electronic devices have to be tested in similar radiation environment before applied in spacecraft. However, it is difficult to test all devices in space or to create a space-like radiation environment. As a result, the experiments on the ground have mainly relied on the tandem accelerator and the cyclotron accelerator. The cyclotron accelerators usually use an ECR ion source for injection, which mean that ion species are more complex than the tandem accelerators. It makes identification difficult by mass spectrometer because the ECR ion source injected different ions with the similar charge-mass ratio into the cyclotron accelerator at the same time. We need to find a new way to distinguish the ions with similar charge-mass ratio in the cyclotron accelerators. There are some studies about the collisions between fast heavy ions and atom targets. When the fast highly charge ion collided with atom targets, they both will emit the characteristic X-ray due to the electron transitions in different shells. Thus it is possible to identify the ions by their different characteristic X-ray spectra. An experiment design was carried out to identify Xe using this technique by these considerations, including the Xe cross section by different atom targets, the characteristic X-ray energy, the photo detectors, and other factors. Firstly, Ag and Mo were chosen as atom targets according to previous experimental data on the X-ray yield of Xe colliding with different atoms. Secondly, the HPGe detector was chosen to detect the X-ray according to the comparison of the characteristic X-ray of Xe, Ag and Mo, and the energy resolution required better than 10 keV. Thirdly, the angle of detecting X-ray would affect the X-ray energy gently. Another the Mylar/Kapton film will degenerate the X-ray intensity similarly, the Mylar film has more strength in a vacuum condition. Finally, an experimental layout figure was draw according to all above the considerations. In conclusion, this work is a preliminary development of a heavy ion identification device. It could be useful for the analysis of mixed heavy ions in the ECR ion source, which is used in test experiments for the single event effect.

The neutron-induced single event effect affects the reliability of electronic devices used in aircraft and ground nuclear facilities. With the progress of semiconductor technology, device feature sizes become smaller and more integrated, radiation sensitivity increases and neutron single event effects become more of an emphasis. To evaluate the performance of electronic devices against neutron single event effects, ground-based neutron irradiation experiments are the most commonly used method in China and abroad. The quasi-monoenergetic neutron is an important neutron source for studying the law and mechanism of the neutron single event effects. Meanwhile, through irradiation experiments with multi-energy neutron beam, the energy dependence curve of the neutron single event effect cross section can be obtained, which can be used to predict the error rate of electronic devices exposed to various neutron radiation environments. Systematic experimental studies of the energy dependence of the neutron single event effect cross section have not been carried out in China, mainly due to the fact that there are few neutron sources suitable for conducting neutron single event effect experiments in China, especially the long-term lack of quasi-monoenergetic neutron sources above 20 MeV. In recent years, with the gradual completion and commissioning of several medium- and high-energy proton accelerators in China, quasi-monoenergetic neutron experimental research has become increasingly available. Theoretical simulation studies prior to the implementation of experimental studies. Based on the nuclear reaction theory, the secondary neutron yield and the neutron single energy peak yield were studied with 50-500 MeV proton and lithium bombardment. The trend of lithium target thickness was calculated by SRIM software with 1.3 MeV proton energy loss in lithium target. The thickness of lithium target with proton energy loss of 2 MeV, secondary neutron yield and neutron energy spectrum in different emission directions were simulated by Monte Carlo method for 50-500 MeV proton. The simulation results show that quasi-monoenergetic neutrons in 0° direction have the best monochromaticity, the neutron fluence rate can reach 104-105 cm-2·s-1 and the proportion of single energy peak is about 50%, for the position of 5 m from the Li target, when the proton intensity is 1 μA and the target thickness is 2 MeV proton energy loss, which can meet the research requirements of neutron single event effect. In conclusion, this work provides theoretical guidance for the design of quasi-monoenergetic neutron targets, beamlines and experimental terminals for neutron single event effect experiments, as well as for the implementation of neutron single event effect irradiation experiments.

With the development of space technology and semiconductor technology, more and more microelectronic devices are used in spacecraft. Heavy ions and protons are two main particles that cause single event effect (SEE) in devices. Heavy ions cause SEE mainly through direct ionization. In most cases, protons have too low linear energy transfer (LET) to cause SEE directly, and they induce SEE through the ionization of the secondary ion products created by nuclear reactions between protons and device materials. The relationship between proton and heavy ion SEE physical mechanism gives us a chance to calculate proton SEE cross-sections from heavy ion experiment data and vice versa. Most of past researches have focused on predicting proton SEE cross-sections from heavy ion SEE cross-sections. However, there are few studies on predicting heavy ion SEE cross-sections based on proton ones. At present, there are the following problems in heavy ion SEE experiments. Firstly, the device needs to be decaped or background before irradiation, which costs time and money, especially for new flip-chip devices, it is difficult to remove the package because of their complex structure. Secondly, due to the short range of heavy ions in the air, the use of low energy heavy ions in experiments requires vacuum environment, but vacuum pumping and breaking consume much time. The proton SEE experiments don’t have these problems, so it is necessary to carry out the research on the method of predicting heavy ion SEE cross-sections from proton ones. Here, a method was proposed to predict heavy ion SEE cross-sections based on proton ones. The theoretical relationship between heavy ion and proton SEE cross-sections was obtained, proton SEE cross-sections can be obtained by integrating heavy ion ones with equivalent LET spectra, and the calculation method for predicting the heavy ion SEE cross-sections was established based on their theoretical relationship. The key of the calculation method is the equivalent LET spectrum of deposited energy of proton incident device. The problem of calculating heavy ion SEE cross-sections from proton SEE cross-sections is transformed into the problem of solving the equation, whose unknows are the four parameters of Weibull function which describe the change of heavy ion SEE cross-sections with LET, and uses particle swarm optimization (PSO) algorithm to solve the problem. Three static random-access memories (SRAMs) with different feature sizes was selected to verify this method, and the results are in good agreement with their heavy ion SEE experimental data. This method provides a new way to obtain heavy ion SEE cross-sections of microelectronic devices, especially for flipchip devices.

As the core of high-voltage direct-current transmission technology, the DC converter valve and its key power device thyristor face a high risk of failure caused by atmospheric neutron when operating in high-altitude areas. The atmospheric neutron failure rate of thyristors used at high altitudes can be quantitatively evaluated by conducting accelerated irradiation tests. The accelerated irradiation experiments of 8.5 kV/5 kA thyristor for DC transmission were carried out at different temperatures by using the China spallation neutron source. The atmospheric neutron-induced single-event burnout (SEB) for thyristor was verified by experiments. It is manifested as a sudden surge in reverse bias leakage current during irradiation, and the device loses its high voltage blocking ability. The failure rates of thyristor caused by atmospheric neutrons were also evaluated based on the accelerated irradiation experimental results. The reverse bias voltages and junction temperatures of thyristor are the key factors affecting the failure rates. The atmospheric neutron-induced failure rates increase exponentially with the reverse bias voltage. The atmospheric neutron failure rate of the 8 500 V thyristor operating at 4 350 V will reach 673 FIT at room temperature at sea level; when the bias voltage drops to 4 100 V (a decrease of about 5.7%), the atmospheric neutron failure rate can be reduced to 11 FIT. In addition, the failure rate increases with the decrease of temperature. The failure rate at 5℃ is nearly 6 times higher than that at 25℃ when the device is biased at 50% of the rated voltage. Based on TCAD simulations, the failure mechanism of thyristor caused by irradiation is further verified. The simulation results show that the SEB failure is directly related to the avalanche breakdown effect-induced by the incident radiation particles. For radiation-induced SEB failure of thyristors, the sensitive region is the N-drift/P-substrate junction depletion region (corresponding to the electric field concentration region under reverse bias of thyristors). When radiation particles are incident into the sensitive region, it can cause the concentration of electric field near the incident location, resulting in additional electric field spikes. If the peak of the electric field exceeds the critical electric field Ec (about 1.64×105 V/cm), it will induce avalanche breakdown. The high voltage reverse bias high current state caused by avalanche breakdown ultimately leads to the failure of the thyristor. The avalanche breakdown effect is positively correlated with the reverse bias voltage of thyristor and negatively correlated with the junction temperature. This is consistent with the variation of atmospheric neutron failure rates with bias voltages and junction temperatures. [ABSTRACT FROM AUTHOR]

Traditionally, studies have primarily focused on single event effects in aerospace electronics. However, current research has confirmed that atmospheric neutrons can also induce single event effects in China's advanced technology relay protection devices. Spallation neutron irradiation tests on a Loongson 2K1000 system-on-chip based relay protection device have revealed soft errors, including abnormal sampling, refusal of operation and interlock in the relay protection device. Given the absence of standardized evaluation methods for single event effects on relay protection devices, the following research emphasizes the use of Monte Carlo simulation and software fault injection. Various types of single event upsets, such as single bit upsets, dual bit upsets, and even eight bit upsets, were observed in Monte Carlo simulations where atmospheric neutrons hit the chip from different directions (top and bottom). The simulation results indicated that the single event effect sensitivity of the relay protection device was similar whether the neutron hit from the top or the bottom. Through software fault injection, the study also identified soft errors caused by neutron induced single event upsets on the Loongson 2K1000 system, including failure to execute, system halt, time out, and error result. And the soft error number of system halts and error results exceeded that of time outs and failures to execute in all three tested programs. This research represents a preliminary assessment of single event effects on relay protection devices and is expected to provide valuable insights for evaluating the reliability of advanced technology relay protection devices. [ABSTRACT FROM AUTHOR]

In space applications, electronics must function while being strongly radiated. In this work, the radiation hardness property of the planar two-terminal nanoscale air channel device (NACD), which is a device of vacuum electronics, was demonstrated. Specifically, the total ionizing dose (TID) effect and single-event effects (SEEs) on the NACD were investigated. X-ray and pulse laser were utilized as the sources of TID radiation and SEE radiation, respectively. No significant degradation was observed after 1 Mrad-(Si) X-ray radiation, and no single-event transient phenomenon was detected at the pulse laser energy up to 5 nJ. Additionally, the physical mechanism of radiation hardness in the NACD was illustrated by theoretical analysis and finite element simulation. Taken together, the proposed work shows that the radiation hardness property of the NACD may have a prospect in deep space and nuclear energy applications. [ABSTRACT FROM AUTHOR]

Copyright of Journal of National University of Defense Technology / Guofang Keji Daxue Xuebao is the property of NUDT Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A multi-layer design is applied to mitigate single event effect (SEE) in a 28 nm System-on-Chip (SoC). It depends on asymmetric multiprocessing (AMP), redundancy and system watchdog. Irradiation tests utilized 70 and 90 MeV proton beams to examine its performance through comparative analysis. Via examining SEEs in on-chip memory (OCM), compared with the trial without applying the multi-layer design, the test results demonstrate that the adopted multi-layer design can effectively mitigate SEEs in the SoC.

A fully depleted silicon-on-insulator (FDSOI) device is a promising structure for future ultrascaled devices because of its high radiation resistance. The buried oxide (BOX) layer of an FDSOI device not only enhances its robustness against single event effects (SEE) but also greatly reduces its ability to resist the effect of the total ionizing dose (TID). We studied factors such as the thickness of BOX layers and the bias state of FDSOI devices and proposed a 22 nm N-type FDSOI 2D device structure. The method of adding fixed charges to the BOX layer and adding state charges to the interface was used to simulate the TID effect. We showed that the thinner the BOX layer, the better the device's ability to resist the effects of the TID. Increasing the total radiation dose causes the electron density of the channel to increase, indicating that the electron mobility of the channel is degraded. Because a large number of electrons are generated by irradiation, their density increases, causing a large number of electrons to collide with each other and scatter under a bias voltage, resulting in decreased electron mobility. By activating the built-in radiation model of the Sentaurus next-generation technology computer-aided design (TCAD) simulation tool, the device was used to simulate the TID effect under different doses in different bias states (OFF, ON, and transmission). The results showed that the most unappealing bias state of the TID effect for the short-channel N-type FDSOI device is the off state. This research provides new insights into the TID for FDSOI devices and can provide guidelines for future applications of radiation-hardened FDSOI-based circuits. The study of single particle effects plays an important role in the study of image sensors in space stations. [ABSTRACT FROM AUTHOR]

As the manufacturing process level of semiconductor devices continues to improve, the device size gradually decreases, and the devices are affected by the single event effect more and more severely. In this paper, the physical process of single particle incident N-channel Metal-Oxide-Semiconductor Field-Effect Transistor (NMOSFET) is simulated. By changing the particle incidence position, incidence angle, LET value, and temperature, the transient current variation with time is obtained, and the susceptibility of the device to single event effect under the action of four factors is analyzed, which provides the basis for the next research of the device against single event effect and ideas for the radiation hardening of semiconductor devices. In addition, in these experiments, there were bimodal-shaped current pulses that were different from single peak transient current pulses. Therefore, a new model describing the bimodal single event transient (SET) current waveform was proposed, which can be used as a current source model in circuit simulation and help to predict the ability of the circuit to resist the single event effect. [ABSTRACT FROM AUTHOR]

A method for calculating the cross-section for single event effect (SEE) in the electronics operation is proposed; it is caused by secondary ions — products of the interaction between a high-energy proton with the atomic nucleus of one of the materials of an integrated circuit. To estimate the excess charge generated in this case, the contribution of all secondary ions, including those born outside the sensitive layer, is taken into account in the model. Along with the traditional approach based on inelastic energy losses, the model considers the process of atom ionization in the approximation of the effective ion charge. The new method gives lower values of the number of electron–hole pairs and the SEE cross-section. [ABSTRACT FROM AUTHOR]

The reliability of nanoscale electronic systems is important in various applications. However, they are becoming increasingly vulnerable to atmospheric neutrons. This research conducted spallation neutron irradiations on a Xilinx Zynq-7000 system on a chip using the China Spallation Neutron Source. The results were analyzed in combination with a Monte Carlo simulation to explore the impact of atmospheric neutrons on the single event effects of the target system on chip. Meanwhile, the contribution of thermal neutrons to the chip's single event effect susceptibility was also assessed. It was found that absorbing thermal neutrons with a 2 mm Cd sheet can protect against the single event effect on the system on the chip by about 44.4%. The effects of B and Hf elements, inside the device, on a single event effect of the Xilinx Zynq-7000 system on chip were evaluated too. Additionally, it was discovered that 10B interacting with thermal neutrons was the primary cause of the thermal neutron-induced single event effect in the system on chip. Although Hf has a high neutron capture cross section, its presence does not significantly affect the sensitivity to single event effects. However, during atmospheric neutron irradiation, the presence of Hf increases the possibility of depositing the total dose in the tested chip. [ABSTRACT FROM AUTHOR]

With the rapid development of semiconductor technology, the reduction in device operating voltage and threshold voltage has made integrated circuits more susceptible to the effects of particle radiation. Moreover, as process sizes decrease, the impact of charge sharing effects becomes increasingly severe, with soft errors caused by single event effects becoming one of the main causes of circuit failures. Therefore, the study of sensitivity evaluation methods for integrated circuits is of great significance for promoting the optimization of integrated circuit design, improving single event effect experimental methods, and enhancing the irradiation reliability of integrated circuits. In this paper, we first established a device model for the charge sharing effect and simulated it under reasonable conditions. Based on the simulation results, we then built a neural network model to predict the charge amounts in primary and secondary devices. We also propose a comprehensive automated method for calculating soft errors in unit circuits and validated it through TCAD simulations, achieving an error margin of 2.8–4.3%. This demonstrated the accuracy and effectiveness of the method we propose.

This work presents a new mitigation technique for radiation induced soft errors in Null Convention Logic (NCL) gates. Asynchronous design including NCL gates can be significantly advantageous in terms of power efficiency, high performance and noise tolerance. However, technology scaling may increase the vulnerability of these gates to particle strikes. This work proposes a Transmission Gate (TG) based technique to suppress glitches caused by particle strikes in NCL gates. The use of the proposed TG significantly filters out the glitch at the output of an NCL gate and prevents it from propagating to other gates. This technique has potential to eliminate soft errors using a small area overhead. [ABSTRACT FROM AUTHOR]

The effect of total dose radiation on the single event effect of uniaxial strained Si Nano channel metal oxide semiconductor field effect transistor (NMOSFET) was studied by TCAD simulation. By comparing the experimental results, the TCAD simulation model of the 50 nm strained Si NMOS device is established. The model is used to simulate the off-state single event effect (Vds = 0.05) of NMOSFET under the total dose radiation. The results show that total dose radiation increases the body potential of NMOSFET devices and intensifies the single event transient process of NMOSFET devices. The transient current increases by 4.88% and the drain charge increases by 29.15% under the total dose of 2KGy, which indicates that the effect of total dose radiation on the single event effect is the main factor affecting the collection of drain charge. Therefore, the experimental results and the established model provide good reference for the study of irradiation reliability of the uniaxial strained Si Nano NMOSFET and the application of strained integrated circuits. [ABSTRACT FROM AUTHOR]

In this paper, the effects of different factors, including the heavy ions striking location, incident angle, linear energy transfer (LET) value, projected range, ambient temperature and bias state, on the single event transient introduced by heavy ions irradiation in the SiGe heterojunction bipolar transistor (HBT) were investigated by the TCAD simulation. The results show that the current transient peak value, collected charge and carrier type of each terminal are changed by the striking location, incident angle and bias state. The current transient peak value and collected charge increase with the LET value, while they decrease with the ambient temperature. When heavy ions vertically irradiate the collector and substrate, the current transient peak value and collected charge increase with the projected range; therefore, the species of heavy ions should be considered in studying the single event effects of the SiGe HBT induced by heavy ions irradiation. The microphysical mechanism of these factors influencing the single event effects of the SiGe HBT is discussed in this work. [ABSTRACT FROM AUTHOR]

Soft errors are transient errors caused by single-event effects (SEEs) resulting from a strike by high-energy particles acting on sensitive areas of integrated circuits. Soft errors frequently occur in the space environment, adversely affecting the reliability of aerospace-based computing. A recovery process is launched to recover the program when soft errors are detected. A periodic checkpointing recovery approach is widely utilized to prevent soft errors. However, this approach does not consider the detector locations, resulting in a large time overhead. This paper proposes a checkpointing recovery approach for soft errors based on detector locations called DLCKPT. DLCKPT reduces the time overhead by considering detector locations. The experimental results show that the percentage decrease in the time overhead between the DLCKPT and the periodic checkpointing recovery approach is 13.4%. The average recovery rate and average space overhead are 99.3% and 44.4% for the periodic checkpointing recovery approach and 99.4% and 34.6% for the DLCKPT. These results show that the DLCKPT and the periodic checkpointing recovery approach produce comparable results for the recovery rate. The DLCKPT has a lower time overhead and a slightly lower space overhead than the periodic checkpointing recovery approach, demonstrating its effectiveness. [ABSTRACT FROM AUTHOR]

Based on the test site at the Qinghai�Tibet Plateau with an altitude of 4 300 m, atmospheric neutron single event effects of a 65 nm high�speed large�area static random access memory (SRAM) array were measured in real�time. By breaking through key technologies such as effect screening, intelligent remote measurement and control, a total of 39 single�event upset were observed during the 153 d test period, of which multiple�cell upset (MCU) accounts for 23%, and the largest MCU is 9 bits. The contribution ratios of high�energy neutron, thermal neutron and alpha particle were analyzed in detail, and based on the multi�ground neutron flux data, the single�bit upset (SBU) and MCU failure in time (FIT) at Beijing ground and 10 km high�altitude application were deduced. It is found that the main cause of soft error on the ground is the alpha particle. As the altitude increases, the contribution of atmospheric neutron to soft error increases significantly. All MCUs are caused by high�energy neutron, and the MCU FIT value at an altitude of 10 km in Beijing is obviously increased. Its proportion increases from 8% of the ground to 26%. In combination with the device layout, an in�depth analysis of the MCU generation mechanism was carried out. Finally, a goal�oriented optimization method of memory soft error hardening strategy was proposed.

Soft errors induced by radiation are the major reliability threat for SRAM-based field-programmable gate arrays (FPGAs). A more detailed analysis of the soft error sensitivity of the 40 nm SRAM-based FPGA was performed. Experimental methods for the configurable logic module, configure memory cells, and block RAM have been introduced for measuring the single event effects (SEEs) induced by alpha particles using a 241Am radiation source. The single event upset (SEU) and single event functional interrupt (SEFI) cross sections of different functional blocks have been calculated to discuss the failure mechanisms of the FPGA. The SEEs test results for the FPGA device based on the 40 nm CMOS process are significant. [ABSTRACT FROM AUTHOR]

BackgroundBased on the 100 MeV proton cyclotron in the China Institute of Atomic Energy (CIAE), the middle-energy proton irradiation test facility was established and several proton single event effect (SEE) experimental study of micro-and nano-electronic devices were carried out. The proton beam striking the device under test (DUT) is contaminated with neutrons generated as a result of protons interacting with the devices between the accelerator and the DUT. The quality of the proton beam directly affects the effectiveness and accuracy of the experimental cross section of proton SEE.PurposeThis study aims to simulate the proton beam distribution and secondary neutron for intermediate energy proton SEE test.MethodsFirst of all, the geometric model of the proton beam transmission line was established. Then, the Monte Carlo N Particle Transport Code (MCNP) was employed to simulate the proton beam of 100 MeV incidence energy. Results were reduced to the case of single proton incidence, the energy and fluence distribution of proton beams on the sample irradiation plane were obtained, as well as the energy and fluence distribution of the secondary neutrons. Finally, influence of secondary neutrons on the experimental cross section of proton single event effect was analyzed according to the ratio of neutron fluence to proton fluence.Results & ConclusionsSimulation results show the effect of secondary neutrons on the cross section of proton single event effect is insignificant, and the medium energy proton irradiation test facility in CIAE is very suitable for the experimental study of proton single event effects.

Integrated circuits are widely used in space devices, for which we are very concerned about the occurrence of a Single Event Effect (SEE). The Hi'Beam-SEE will be a novel platform for micrometer-level SEE study at the Heavy Ion Research Facility in Lanzhou. The heavy ion positioning system in the Hi'Beam-SEE, based on silicon pixel sensors, accurately localizes each particle within the beam. The laser and heavy ion test results show that the heavy ion positioning system can achieve a spatial resolution of ∼ 2 μ m. This paper will discuss the design and performance of the heavy ion positioning system. [ABSTRACT FROM AUTHOR]

A simple method for the prediction of the heavy ion-induced single event effect cross-section based on proton experimental data has been proposed, which is convenient for flip chips. The method relies on the effective LET spectrum of protons in the sensitive layer of microelectronic devices. Two chips using different packaging technologies are selected to verify this method, and the results obtained by our method are consistent with the heavy ion experimental data. The principle of this method has been analyzed in depth, and the limitations are also given. [ABSTRACT FROM AUTHOR]

A high-speed wireline interfaces, e.g. LVDS (Low Voltage Differential Signaling), are widely used in the aerospace field for powerful computing in artificial satellites and aircraft [19]. This paper describes Bit Error Rate (BER) prediction methodology for wireline data transmission under irradiation environment at the design stage of data transmitter, which is useful in proactively determining if the design circuit meets the BER criteria of the target system. Using a custom-designed LVDS transmitter (TX) to enhance latch-up immunity [42], the relationship between transistor size and BER has been analyzed with focusing on Single Event Effect (SEE) as a cause of the bit error. The measurement was executed under 84Kr17+ exposure of 322.0 MeV at various flux condition from 1 × 103 to 5 × 105 count/cm2/sec using cyclotron facility. For the analysis of the bit error, circuit simulation by SPICE was utilized with expressing the irradiation environment by a current source model. The current source model represents a single event strike into the circuit at drain and substrate junctions in bulk MOSFETs. For the construction of the current source model, a charge collection was simulated at the single particle strike with the creation of 3D Technology CAD (TCAD) models for the MOS devices of bulk transistor process technology. The simulation result of the charge correction was converted to a simple time-domain equation, and the single-event current source model was produced using the equation. The single-event current source was applied to SPICE simulation at bias current related circuits in the LVDS transmitter, then simulation results are carefully verified whether the output data is disturbed enough to cause bit errors on wireline data transmission. By the simulation, sensitive MOSFETs have been specified and a sum of the gate area for these MOSFETs has 29% better correlation than the normal evaluation index (sum of the drain area) by comparison to the actual BER measurement. Through the precise revelation of the sensitive area by SPICE simulation using the current model, it became possible to estimate BER under irradiation environment at the pre-fabrication design stage. [ABSTRACT FROM AUTHOR]

In this paper, a carbon nanotube field effect transistor (CNTFET) based single event upset (SEU) tolerant latch is proposed. The proposed latch can tolerate the effect of particle strike at any of its storage nodes thus making it completely immune to SEU. Presented work focusses on latch design to mask the single event transient (SET) pulses generated in combinational circuits preceding a latch/register in a digital system. In this work, already existing latches are implemented in CNTFET technology and compared with the proposed latch by running a set of simulations using HSPICE. The impact of single event effects (SEEs) on various CNTFET based latches have been investigated and it is observed that the proposed latch is most efficient in filtering SET pulses. The proposed latch is able to filter SET with a maximum pulse width of 12.3 pS. The proposed latch has also been compared with existing latches on the basis of two comprehensive performance metrics referred to as Ability of SET Filtering (AOSF) and Area-Power-Delay-Pulse Product (APDPP). It is observed that the proposed latch demonstrates best AOSF (that is a measure of SET filtering efficiency) of 93.04% among the latches considered for comparison in this work. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) system based on neuron chip with high reliability and low power-consumption is of great importance for long-term space mission and deep space exploration. However, the AI application is challenged by the single event effect of microelectronics including soft error and hard damage upon harsh space radiation. In this work, an AI modelled Pavlov system based on a mixed-signal spike neuron chip has been studied at unit and chip level in response to single event transient injections. The heavy ion beam and laser irradiation were performed to evaluate the single event reliability of the neuron system. The results indicate that the Pavlov neuron chip possesses excellent single event effect immunity and high reliability to space radiation. This work demonstrates that the AI system based on neuron chip is reliable for robotic and unmanned application with space radiation and nuclear exposure environments. • The single event reliability of an AI modelled Pavlov system based on neuron chip was reported for the first time. • The simulations and irradiation analysis indicate the excellent SET resistance of the mixed-signal spicke neuron chip. • The neuron-based AI system is highly reliable in harsh radiation environment and space application. [ABSTRACT FROM AUTHOR]

Single event upset, or Single Event Effect (SEE) is increasingly important as semiconductor devices are entering into nano-meter scale. The Linear Energy Transfer (LET) concept is commonly used to estimate the rate of SEE. The SEE, however, should be related to energy deposition of each stochastic event, but not LET which is a non-stochastic quantity. Instead, microdosimetry, which uses a lineal calculation of energy lost per step for each specific track, should be used to replace LET to predict microelectronic failure from SEEs. Monte Carlo simulation is used for the demonstration, and there are several parameters needed to optimise for SEE simulation, such as the target size, physical models and scoring techniques. We also show the thickness of the sensitive volume, which also correspond to the size of a device, will change the spectra of lineal energy. With a more comprehensive Monte Carlo simulation performed in this work, we also show and explain the differences in our results and the reported results such as those from Hiemstra et al. which are commonly used in semiconductor industry for the prediction of SEE in devices. [ABSTRACT FROM AUTHOR]