- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2019 IEEE 5th International Conference on Wireless and Telematics (ICWT) - Yogyakarta, Indonesia (2019.7.25-2019.7.26)] 2019 IEEE 5th International Conference on Wireless and Telematics (ICWT) - The Behavioral Study of an Optical Injection-Locked Semiconductor Laser under the Influence of Intensity and Phase Noise
摘要： Channel electron multiplier (CEM) and microchannel plate (MCP) detectors are routinely used in space instrumentation for measurement of space plasmas. Our goal is to understand the relative sensitivities of these detectors to penetrating radiation in space, which can generate background counts and shorten detector lifetime. We use keV -rays as a proxy for penetrating radiation such as -rays, cosmic rays, and high-energy electrons and protons that are ubiquitous in the space environment. We find that MCP detectors are times more sensitive to keV -rays than CEM detectors. This is attributed to the larger total area of multiplication channels in an MCP detector that is sensitive to electronic excitation and ionization resulting from the interaction of penetrating radiation with the detector material. In contrast to the CEM detector, whose quantum efficiency keV -rays is found to be 0.00175 and largely independent of detector bias, the quantum efficiency of the MCP detector is strongly dependent on the detector bias, with a power law index of 5.5. Background counts in MCP detectors from penetrating radiation can be reduced using MCP geometries with higher pitch and smaller channel diameter.
关键词： gamma-ray effects,radiation effects,plasma measurements,Electron multipliers
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - A Sunflower Receiver for Hybrid Photovoltaic-Solar Thermal Energy Conversion
摘要： Field-programmable gate arrays (FPGAs) have been shown to provide high computational density and efficiency for many computing applications by allowing circuits to be customized to any application of interest. FPGAs also support programmability by allowing the circuit to be changed at a later time through reconfiguration. There is great interest in exploiting these benefits in space and other radiation environments. FPGAs, however, are very sensitive to radiation and great care must be taken to properly address the effects of radiation in FPGA-based systems. This paper will highlight the effects of radiation on FPGA-based systems and summarize the challenges in deploying FPGAs in such environments. Several well-known mitigation methods will be described and the unique ability of FPGAs to customize the system for improved reliability will be discussed. Finally, two case studies summarizing successful deployment of FPGAs in radiation environments will be presented.
关键词： radiation effects,radiation hardening,field programmable gate arrays,integrated circuit reliability,Fault-tolerant systems
更新于2025-09-19 17:13:59
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[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - An 150 GHz Waveguide Bandpass Filter Based on Micro-satellite Platform
摘要： Field-programmable gate arrays (FPGAs) have been shown to provide high computational density and efficiency for many computing applications by allowing circuits to be customized to any application of interest. FPGAs also support programmability by allowing the circuit to be changed at a later time through reconfiguration. There is great interest in exploiting these benefits in space and other radiation environments. FPGAs, however, are very sensitive to radiation and great care must be taken to properly address the effects of radiation in FPGA-based systems. This paper will highlight the effects of radiation on FPGA-based systems and summarize the challenges in deploying FPGAs in such environments. Several well-known mitigation methods will be described and the unique ability of FPGAs to customize the system for improved reliability will be discussed. Finally, two case studies summarizing successful deployment of FPGAs in radiation environments will be presented.
关键词： radiation effects,radiation hardening,Fault-tolerant systems,integrated circuit reliability,field programmable gate arrays
更新于2025-09-19 17:13:59
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Transient and Steady-State Radiation Response of Phosphosilicate Optical Fibers: Influence of H2 Loading
摘要： The radiation response of a phosphorus-doped multimode optical fiber is investigated under both transient (pulsed X-rays) and steady state (γ-rays and X-rays) irradiations. The influence of a H2 pre-loading on the fiber radiation induced attenuation (RIA) in the 300 nm - 2000 nm wavelength range has been characterized. To better understand the impact of this treatment, online behaviors of fiber samples containing different amounts of gas are compared from glass saturation (100%) to less than 1%. In addition to these in situ experiments, additional post-irradiation spectroscopic techniques have been performed such as electron paramagnetic resonance or luminescence measurements to identify the different point defects responsible for the induced losses and their H2 dependence. All our data at room temperature (RT) highlight a strong positive impact of H2, even at very low concentrations, on the RIA. Hydrogen quickly passivates (t<1 s) most of the defects responsible for the visible – near-IR RIA, mainly phosphorus oxygen hole centers (POHC) and P1 defects. However, one year after the H2-loading at RT or when operating at liquid nitrogen temperature, the RIA levels of the not-treated and H2-loaded fiber become comparable. The obtained results provide a better understanding of the potential and limitations of H2-loading treatment to design radiation hardened fiber links.
关键词： temperature,point defects,phosphorus,H2-loading,X-rays,radiation effects,optical fibers,pulsed X-rays
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Highly Reliable Multi-Port Smart Inverter Modules for PV-Based Energy Systems
摘要： A variety of fault emulation systems have been created to study the effect of single-event effects (SEEs) in static random access memory (SRAM) based field-programmable gate arrays (FPGAs). These systems are useful for augmenting radiation-hardness assurance (RHA) methodologies for verifying the effectiveness for mitigation techniques; understanding error signatures and failure modes in FPGAs; and failure rate estimation. For radiation effects researchers, it is important that these systems properly emulate how SEEs manifest in FPGAs. If the fault emulation systems does not mimic the radiation environment, the system will generate erroneous data and incorrect predictions of behavior of the FPGA in a radiation environment. Validation determines whether the emulated faults are reasonable analogs to the radiation-induced faults. In this paper we present methods for validating fault emulation systems and provide several examples of validated FPGA fault emulation systems.
关键词： radiation effects,fault diagnosis,field programmable gate arrays,Emulation
更新于2025-09-16 10:30:52
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Steady State X-Ray Radiation Induced Attenuation in Canonical Optical Fibers
摘要： So-called canonical optical fibers are samples especially designed to highlight the impact of some manufacturing process parameters on the radiation responses. Thanks to the results obtained on these samples, it is thus possible to define new procedures to better control the behaviors of optical fibers in radiation environments. In the present work, we characterized the responses, under steady state X-rays, of canonical samples representative of the most common fiber types differing by their core-dopants: pure silica, Ge, Al and P. Their radiation induced attenuation (RIA) spectra were measured online at both room temperature (RT) and liquid nitrogen temperature (LNT), in the energy range [~0.6 - ~3.0] eV (~2100 nm - ~410 nm), highlighting the RIA growth kinetics during the fiber exposure up to an accumulated dose of ~200 Gy(SiO2) at a constant dose rate of 100 mGy/s at RT. At LNT, the deposited doses varied between 100 and 180 Gy, with a time dependent dose rate. In order to understand the origin of the excess losses and the difference between the RIA spectral shapes observed at the two temperatures, a spectral decomposition of the optical losses has been performed using a set of Gaussian absorption bands related to the already known point defects. As a result, if the RIA in the visible domain is quite well understood, the knowledge on RIA origin in the near-IR remains incomplete, justifying new and deeper studies to clarify the fibers response under steady state irradiation.
关键词： point defects,radiation effects,attenuation,pure silica core and doped optical fibers,canonical samples
更新于2025-09-16 10:30:52
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[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Theory and Experiment of a Compact Waveguide Polarization Diplexer
摘要： A variety of fault emulation systems have been created to study the effect of single-event effects (SEEs) in static random access memory (SRAM) based field-programmable gate arrays (FPGAs). These systems are useful for augmenting radiation-hardness assurance (RHA) methodologies for verifying the effectiveness for mitigation techniques; understanding error signatures and failure modes in FPGAs; and failure rate estimation. For radiation effects researchers, it is important that these systems properly emulate how SEEs manifest in FPGAs. If the fault emulation systems does not mimic the radiation environment, the system will generate erroneous data and incorrect predictions of behavior of the FPGA in a radiation environment. Validation determines whether the emulated faults are reasonable analogs to the radiation-induced faults. In this paper we present methods for validating fault emulation systems and provide several examples of validated FPGA fault emulation systems.
关键词： radiation effects,fault diagnosis,field programmable gate arrays,Emulation
更新于2025-09-16 10:30:52
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Response of Waveguide-Integrated Germanium-on-Silicon p-i-n Photodiodes to Neutron Displacement Damage
摘要： The effects of 14-MeV neutron displacement damage (DD) on waveguide-integrated germanium-on-silicon p-i-n photodiodes (PDs) for silicon photonics have been investigated up to fluences of 7.5×1012 n/cm2 (14 MeV), or 1.4×1013 n1-MeVeq /cm2(Si). The study includes measurements of dark current-voltage characteristics across temperature from 150-375 K, measurements of PD junction capacitance, spectral response measurements from 1260 nm to 1360 nm, and frequency response measurements. The devices are found to be susceptible to DD-induced carrier removal effects; however, they also continue to operate without meaningful impact to performance for the DD dose levels examined. Since the PD test chips include silicon photonic integrated grating couplers and waveguides which carry the optical signal to the PD, some assessment of the impact of DD on these passive devices can also be inferred. This work does not examine the short-term annealing or transient behavior of the DD, and instead has only considered the lasting damage that remains after any initial period of room temperature annealing.
关键词： displacement damage,photonics,Radiation effects,neutron radiation,photodiodes,optoelectronic devices
更新于2025-09-12 10:27:22
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Effect of Proton Radiation on Ultra-Wide Bandgap AlN Schottky Barrier Diodes
摘要： Lateral Pd/n-AlN Schottky barrier diodes (SBDs) were fabricated and subjected to 3 MeV proton irradiation at various fluences. Electrical and material characterization analysis was performed before and after each radiation fluence to quantify the change in device characteristics. It was found that the SBDs performed reliably up to a proton irradiation fluence of 5×1013 cm-2, with little or no change in the key device performance such as current, turn-on voltage, ideality factor, and breakdown voltage, etc. The electrical characteristics of the SBDs was well predicted using a standard thermionic emission theory. The performance of the SBDs showed a significant degradation after a high-fluence irritation of 5×1015 cm-2, where the current of the SBDs dropped two orders of magnitude. Material and surface characterizations, including atomic force microscopy and X-ray diffraction, indicated a consistent degradation in the AlN bulk crystal quality and a drastic increase in surface roughness. These results provide valuable information on the radiation properties of AlN electronics and can serve as important references for the future development of high performance AlN devices for extreme environment applications.
关键词： surface roughness,leakage current,radiation effects,Aluminum nitride,breakdown voltage,barrier height,Schottky barrier diodes,ideality factor,turn on voltage
更新于2025-09-11 14:15:04
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Review of Measured Photon Detection Efficiencies of Microchannel Plates
摘要： In this work, we examine the history of detection efficiency measurements of photons (soft to hard X-rays and beyond) with microchannel plates (MCPs). We investigate the detection efficiency as a function of photon energy over a wide energy range, from a few hundred eV up to 20 MeV. We also investigate detection efficiency as a function of incident angle onto the MCP. We interpreted the published efficiency data measured with a variety of MCPs, the use of MCP coatings for enhancement of X-ray quantum detection efficiency, and discuss theoretical expectations based on the main photon interactions with matter: the photoelectric effect, Compton scattering, and pair production. Contributing to the published literature at the highest end of the energy range, we also discuss our photon detection efficiency experiments from 2.5 to 20 MeV and theoretical implications.
关键词： Radiation environment,Space radiation environments,Radiation effects,Space instrumentation,Detectors,Space radiation
更新于2025-09-09 09:28:46