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We present the first active visible blind ultraviolet (UV) photodetector based on zinc oxide (ZnO) nanostructured AlGaN/GaN high electron mobility transistors (HEMTs). The ZnO nanorods (NRs) are selectively grown on the gate area by using hydrothermal method. It is shown that ZnO nanorod (NR)-gated UV detectors exhibit much superior performance in terms of response speed and recovery time to those of seed-layer-gated detectors. It is also found that the best response speed (~10 and~190 ms) and responsivity (~1.1×105 A/W) were observed from detectors of the shortest gate length of 2 µm among our NR-gated devices of three different gate dimensions, and this responsivity is about one order higher than the best performance of ZnO NR-based UV detectors reported to date. 相似文献
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探测器响应度直接影响双向光收发组件(bi-directional optical sub-assembly,BOSA)的性能,探测器端的耦合和封装在BOSA生产中占据重要地位。为了系统分析BOSA生产中各偏移因素对探测器端耦合的影响,选择探测器电流响应度作为耦合标准进行实验,并通过分析实验结果来得出BOSA探测器端耦合和封装过程中的改进措施。参考BOSA的实际光路,建立光纤-波片-芯片耦合模型,模拟了光束偏移与耦合效率的关系;研究了BOSA耦合和封装工艺中产生的偏移,并分析它们对探测器端耦合效率的影响。随后使用自动耦合设备,对BOSA探测器端进行耦合实验,并分析波片角度偏移、波片与探测器透镜的高度差、探测器透镜水平偏移对耦合效率的影响。实验结果表明:探测器透镜水平偏移对耦合效率的影响最大,波片角度偏移、波片与探测器透镜的高度差对耦合效率的影响较小。研究结果为BOSA探测器端的耦合和封装提供了系统的理论指导,对BOSA的实际生产有一定参考价值。 相似文献
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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。 相似文献
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Photodetectors: Ultrathin SnSe2 Flakes Grown by Chemical Vapor Deposition for High‐Performance Photodetectors (Adv. Mater. 48/2015) 下载免费PDF全文
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正This paper explores an alternative to the standard method of studying the responsivities(the input-output gain) and other behaviours of detectors at low electron energy.The research does not aim to compare the results of differently doped n~+p detectors;its purpose is to provide an alternative characterization method(using scanning electron microscopy) to those used in previous studies on the responsivity of n~+p doped detectors as a function of the electron radiation energy and other interface parameters. 相似文献
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N. Noulkow R. D. Taubert P. Meindl J. Hollandt 《International Journal of Thermophysics》2009,30(1):131-143
At the Physikalisch-Technische Bundesanstalt (PTB), absolutely-calibrated filter radiometers based on silicon photodiodes
are routinely used for thermodynamic temperature determinations of blackbodies in the range from the zinc fixed point (FP)
(419 °C) up to 3,000 °C. To extend the temperature range down to the tin FP (232 °C), we have designed two new filter radiometers
based on indium gallium arsenide (InGaAs) photodiodes with center wavelengths at 1,300 nm and 1,550 nm. For the absolute calibration
of the spectral irradiance responsivity of the new InGaAs filter radiometers, the spectral responsivity measurement in the
near-infrared (NIR) spectral range has been significantly improved. With a newly developed tuneable laser and monochromator-based
cryogenic radiometer facility, the relative standard uncertainty of the NIR spectral responsivity has been reduced from 0.17 %
to about 0.03 %. By using the calibrated InGaAs filter radiometer in conjunction with the large-area double sodium heat pipe
of the PTB, the first results for the difference between the thermodynamic temperature T and the ITS-90 temperature T
90 in the temperature range from the zinc FP up to the aluminum FP (660 °C) are presented. The values for T – T
90 determined with the new InGaAs filter radiometers are consistent within their relative standard uncertainty of about 30 mK
at 419 °C to about 60 mK at 660 °C.
References to commercial products are for identification purposes only and constitute neither endorsement nor representation
that the item identified is the best available for the stated purpose. 相似文献