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Analysis of high-temperature performance of 4H-SiC avalanche photodiodes in both linear and Geiger modes

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Chinese Physics B 2023年第3期32卷 583-588页

作者：周幸叶吕元杰郭红雨顾国栋王元刚梁士雄卜爱民冯志红 National Key Laboratory of ASIC Hebei Semiconductor Research InstituteShijiazhuang 050051China

The high-temperature performance of 4H-SiC ultraviolet avalanche photodiodes(APDs)in both linear and Geiger modes is extensively investigated.During the temperature-dependent measurements,a fixed bias voltage is adopted for the device samples,which is much more practical and important for high-temperature applications.The results show that the fabricated 4H-SiC APDs are very stable and reliable at high temperatures.As the temperature increases from room temperature to 425 K,the dark current at 95%of the breakdown voltage increases slightly and remains lower than40 pA.In Geiger mode,our 4H-SiC APDs can be self-quenched in a passive-quenching circuit,which is expected for highspeed detection systems.Moreover,an interesting phenomenon is observed for the first time:the single-photon detection efficiency shows a non-monotonic variation as a function of temperature.The physical mechanism of the variation in hightemperature performance is further analyzed.The results in this work can provide a fundamental reference for researchers in the field of 4H-SiC APD ultraviolet detectors.

关键词： 4H-SiC avalanche photodiode ultraviolet detector high temperature

Slow-rise and fast-drop current feature of ultraviolet response spectra for ZnO-nanowire film modulated by water molecules

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Chinese Physics B 2012年第3期21卷 490-496页

作者：任守田王强赵锋曲士良 Department of Optoelectronic Science Harbin Institute of Technology at Weihai

This study describes the fabrication of ZnO-nanowire films by electro-chemical anodization of Zn foil. The ZnO films are characterized by field emission scanning electron microscopy, X-ray diffraction patterns, and transmission electron microscopy, respectively. The ultraviolet （UV） photo-response properties of the surface-contacted ZnO film are studied through the current evolution processes under different relative humidities. Unlike the usually observed current spectra of the ZnO films, the drop time is shorter than the rise time. The photo-conductivity gain G and the response time T are both increased with the increase of the applied bias. The photo-conductivity gain G is lowered with the increase of the environmental humidity, while the response time τ- is increased. These results can be explained by considering three different surface processes： 1） the electron-hole （e-p） pair generation by the UV light illumination, 2） the following surface O2 species desorption, and 3） the photo-catalytic hydrolysis of water molecules adsorbed on the ZnO surface. The slow-rise and fast-drop current feature is suggested to originate from the sponge-like structure of the ZnO nanowires.

关键词： electro-chemical anodization ZnO nanowires ultraviolet detector

ultraviolet irradiance calibration system based on standard detector

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Ultraviolet irradiance calibration system based on standard ...

A simulation of doping and trap effects on the spectral response of AlGaN ultraviolet detectors

国防光电子论坛空间光信息与组网技术及应用研讨会

作者： Facai Zhao Quanshe Sun Shaoshui Wang Guoquan Wang Science and Technology on Electronic Test & Measurement Laboratory The 41st Research Institute of China Electronics Technology Group Corporation

We present a special facility for accurate calibration of instrument’s irradiance responsivity in ultraviolet spectral region to overcome the troubles caused by the weak ultraviolet response of most spectral radiometer and poor signal-to-noise ratio. In this system, a Seya-Namioka monochromator with a small f-number is designed to get more energy as an irradiance source. Reference standard irradiance detectors, calibrated against to primary standard detector traceable to cryogenic radiometer for spectral power responsivity, are used to determine the irradiance at a reference plane. The typical combined standard uncertainties in irradiance responsivity calibrations using this system can be 2.3%.

关键词： Instrumentation design Irradiance calibration Optical design ultraviolet detector

来源： cnki会议评论

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Journal of Semiconductors 2012年第3期33卷 20-23页

作者： Sidi Ould Saad Hamady LMOPS University Paul Verlaine-Metz and SUPELEC-2 Rue Edouard Belin57070 MetzFrance

We study,by means of numerical simulation,the impact of doping and traps on the performance of the＂solar blind＂ultraviolet Schottky detector based on AlGaN.We implemented physical models and AlGaN material properties taken from the literature,or from the interpolation between the binary materials（GaN and AlN） weighted by the mole fractions.We found that doping and traps highly impact the spectral response of the device,and in particular a compromise in the doping concentration must be reached in order to optimize the spectral response of the detector.These results give us a powerful tool to quantitatively understand the impact of elaboration and processing conditions on photodetector characteristics,and thus identify the key issues for the development of the technology.

关键词： simulation AlGaN ultraviolet detector spectral response