摘要
在漂移扩散方程的基础上建立了AlGaNp-i-n光电探测器的物理模型,分析了多种结构AlGaNp-i-n光电探测器的光谱响应,并讨论了AlGaN/GaN异质结界面极化效应对太阳盲区p-GaN/i-Al0.33Ga0.67N/n-GaN倒置异质结结构p-i-n光电探测器(invertedheterostructurephotodetectors,IHPs)UV/Solar选择比(280nm与320nm响应度之比)的影响.结果表明:优化p层是提高器件光谱响应的有效途径;为获得较高的UV/Solar选择比,光伏模式(零偏压)为太阳盲区p-GaN/i-Al0.33Ga0.67N/n-GaNIHPs的最佳工作模式;在光伏模式下考虑极化效应影响时,Ga面p-GaN/i-Al0.33Ga0.67N/n-GaNIHPs器件的UV/Solar选择比可达750,与Tarsa等人报道的三个量级的实验结果基本一致.
The physical model of the AlGaN based p-i-n photodetector is built on the base of the coupled drift-diffusion equation. Spectral responsivity curves of various AlGaN p i n photodetectors and the influence of polarization at the interface of AlGaN/GaN heterostructure on the UV/solar rejection ratios of p-GaN/i-A10.33 Ga0.67 N/n-GaN inverted heterostructure photodetectors（IHPs） are analyzed. The results show that the p-type layer imposes an important influence on the spectra responsivity of the A1GaN based p-i-n photodetecotrs,and the optimization of the p type layer is an effective method of significantly unproving the spectra responsivity. In order to get high UV/solar rejection ratios, the solar-blind IHPs should work best on the unbiased condition. When the polarization is considered with zero blase, the UV/solar rejection ratios of Ga-faced solar-blind p-GaN/i-Al0.33 Ga0.67 N/n-GaN IHPs are 750, which meets the Tarsa＇s experiment result of about three orders of magnitude.
基金
国家重点基础研究发展规划资助项目(批准号:51327020301)~~
