GaN基MSM结构紫外探测器光响应特性

Photo-response in GaN-based MSM UV Detectors

在求解一维电流连续性方程和传输方程的同时考虑表面态陷阱的作用,获得了GaN基MSM结构紫外探测器在稳态光照下的电流随电压变化的解析解,从而导出了其光响应特性主要参数,并解释了电流和响应度随偏压变化的原因和光增益现象。将该模型应用于具体器件,实验测得饱和临界偏压约6 V,稳态电流6×10-8A,响应率0.085 7 A/W,与理论计算较吻合。

A model of currents in GaN-based metal-semiconductor-metal （MSM） UV photodetectors have been obtained in one-dimensional structure using steady-state continuity equations,including the effect of surface states. According to the model, the photocurrent gain is explained,and the influences of the width of depletion regions on the photocurrents as a function of the applied bias voltage are investigated. The saturation bias voltage of - 6 V,stable current of 6 × 10^-8 A and responsivity of 0. 085 7 A/W are experimentally obtained. These results are in good agreement with the experimental ones.