Optically controlled SiCGe/SiC heterojunction transistor with charge-compensation layer

A novel optically controlled SiCGe/SiC heterojunction transistor with charge-compensation technique has been simulated by using commercial simulator.This paper discusses the electric field distribution,spectral response and transient response of the device.Due to utilizing p-SiCGe charge-compensation layer,the responsivity increases nearly two times and breakdown voltage increases 33%.The switching characteristic illustrates that the device is latch-free and its fall time is much longer than the rise time.With an increase of the light power density and wavelength,the rise time and fall time will become shorter and longer,respectively.In terms of carrier lifetime,a compromise should be made between the responsivity and switching speed,the ratio of them reaches maximum value when the minority carrier lifetime equals 90 ns.     

High‐Responsivity Photodetectors Based on Formamidinium Lead Halide Perovskite Quantum Dot–Graphene Hybrid

Highly performance photodetector requires a wide range of responses of the incident photons and converts them to electrical signals efficiently. Here, a photodetector based on formamidinium lead halide perovskite quantum dots (e.g., FAPbBr₃ QDs)–graphene hybrid, aiming to take the both advantages of the two constituents. The FAPbBr₃ QD–graphene layer not only benefits from the high mobility and wide spectral absorption of the graphene material but also from the long charge carrier lifetime and low dark carrier concentration of the FAPbBr₃ QDs. The photodetector based on FAPbBr₃ QD–graphene hybrid exhibits a broad spectral photoresponse ranging from 405 to 980 nm. A photoresponsivity of 1.15 × 10⁵AW⁻¹ and an external quantum efficiency as high as 3.42 × 10⁷% are obtained under an illumination power of 3 µW at 520 nm wavelength. In detail, a high responsivity is achieved in 405–538 nm, while a relatively low but fast response is observed in 538–980 nm. The photoelectric conversion mechanism of this hybrid photodetector is investigated in the view of built‐in electric field from the QD–graphene contact which improves the photoconductive gain.     

红外光谱发射率测量系统的温漂修正方法

针对探测器光谱响应度温漂现象对红外光谱发射率测量系统重复性的影响,分析探测器温度与输出电压之间的变化规律,提出了基于多项式拟合的光谱响应度温漂修正方法。研究探测器自身温度与其光谱响应度的函数关系,对探测器光谱响应度随温度变化的曲线进行数据拟合,得到探测器温度-光谱响应度的拟合方程,计算光谱响应度的温漂修正系数,修正探测器的输出电压,消除光谱响应度温漂现象对探测器输出电压造成的影响。研制光谱响应度温漂修正装置,测得探测器光谱响度的温漂曲线,对比指数拟合曲线和多项式拟合曲线与测量曲线的吻合度,结果表明6阶多项式拟合曲线的一致性较好,提高了基于积分球反射计的光谱发射率测量系统的重复性。     

PIN光电探测器低噪声前置放大电路设计

该文设计了一款PIN光电探测器的低噪声前置放大电路,选用低噪声器件,设计带通滤波电路,实现阻抗匹配,消除噪声。该电路由＋15V和±5V三电源驱动,照射激光波长λ=850nm,光脉冲频率f=10kHz,光脉冲宽度τ=20ns。通过软件仿真及实物测试,达到响应度Re（V/W）≥2×10^5,上升时间Tr（ns）≤13,暗噪声电压峰峰值VN（mV）≤10,闭环增益A（dB）≥60等指标,表明该文方法可以为低噪声前置放大电路设计提供指导。     

The effect of bias light on the spectral responsivity of organic solar cells

The spectral responsivity, S, and the related spectrally resolved photon-to-electron external quantum efficiency, EQE, are standard device characteristics of organic solar cells and can be used to determine the short-circuit current density and power conversion efficiency under standardized test conditions by integrating over the spectral irradiance of the solar emission. However, in organic solar cells S and EQE can change profoundly with light intensity as a result of processes that vary non-linearly with light intensity such as bimolecular recombination of electrons and holes or space charge effects. To determine the S under representative solar light conditions, it is common to use modulated monochromatic light and lock-in detection in combination with simulated solar bias light to bring the cell close to 1 sun equivalent operating conditions. In this paper we demonstrate analytically and experimentally that the S obtained with this method is in fact the differential spectral responsivity, DS, and that the real S and the experimental DS can differ significantly when the solar cells exhibit loss processes that vary non-linearly with light intensity. In these cases the experimental DS will be less than the real S. We propose a new, simple, experimental method to more accurately determine S and EQE under bias illumination. With the new method it is possible to accurately estimate the power conversion efficiency of organic solar cells.     

4H-SiC 雪崩光电探测器中倍增层参数的优化模拟

应用ATLAS模拟软件,设计了吸收层和倍增层分离的（SAM）4H-SiC 雪崩光电探测器（APD）结构。分析了不同外延层厚度和掺杂浓度对器件光谱响应的影响,对倍增层参数进行优化模拟,得出倍增层的最优化厚度为0.26μm,掺杂浓度为9.0×1017cm^-3。模拟分析了APD的反向IV特性、光增益、不同偏压下的光谱响应和探测率等,结果显示该APD在较低的击穿电压66.4V下可获得较高的倍增因子105;在0V偏压下峰值响应波长（250nm）处的响应度为0.11A/W,相应的量子效率为58%;临近击穿电压时,紫外可见比仍可达1.5×103;其归一化探测率最大可达1.5×1016cmHz ^1/2 W^-1。结果显示该APD具有较好的紫外探测性能。     

电极间距对ZnO基MSM紫外光电探测器性能的影响

利用金属有机物化学气相沉积法在蓝宝石衬底上制备了ZnO薄膜。利用Au电极,在ZnO薄膜上制备电极间距不同的金属-半导体-金属结构紫外光电探测器。发现随着电极间距从150μm降至5μm,探测器响应度呈现出从15 mA/W到75 mA/W的明显提高。同时,随着电极间距的减小,器件的I-V曲线线形发生了显著改变。这被归结为电极间距变化改变了器件耗尽区宽度和电极间电阻造成的结果。     

红外接收用PIN硅光电探测器研究

PN二极管是一种常用的光电探测器,其中PIN光电二极管因其体积小、噪声低、响应速度快、光谱响应性能好等特点已作为一个标准件广泛应用于红外遥控接收领域。文章基于半导体材料的光吸收特性和光电效率转换原理,同时结合减反射膜理论,对PIN光电二极管进行研究,通过衬底材料的合理选择,对减反射膜折射率及厚度进行对比实验,验证了SiN膜层较SiO2膜有着更为良好的减反射效果,可以有效提升光敏器件的光电转换效率,同条件下器件的光生电流得到提升,为今后光电器件的生产、开发应用提供了参考。     

基于VO_2薄膜非致冷红外探测器性能研究

用微电子工艺制备了 V O2 溅射薄膜红外探测器 ,在 2 96 K的环境温度中测试了该探测器对 8- 12 μm红外辐射的黑体响应率和噪声电压 ,结果显示该探测器在调制频率为 30 Hz时可以实现探测率 D*=1.89× 10 8cm H z1 /2W- 1 ,热时间常数 τ=0 .0 11s的非致冷红外探测     

太赫兹半导体探测器研究进展

太赫兹（THz）探测器是THz技术应用的关键器件之一.基于半导体的全固态THz量子阱探测器（THzQWIP）具有探测响应速度快、制作工艺成熟、体积小和易集成等优点.文章简要介绍了THz探测器的分类和特点,重点介绍了THzQWIP的工作原理和研究进展.