GaAs MSM光电探测器中电子渡越时间研究

Investigation on Electron Transist Time in GaAs MSM Photodetectors

根据 GaAs 材料的电子漂移速度与电场的非线性关系,研究了 GaAs MsM光电探测器电极间电子渡越时间与掺杂浓度 N_D、栅宽 L_g 和工作电压 V 的关系,结果表明,MSM-PD 电极间电子渡越时间存在极小值。对于电极间距离为3.0μm的 MSM-PD,掺杂浓度为1×10^(14)cm^(-3)的MSM-PD。工作电压为2倍平带电压时,电子渡越时间处于极小值。研究结果为设计高速响应 GaAs MSM 光电探测器及建立器件光电响应模型提供了依据。

Using the method of computer-aided analysis,the transist time as a function of the applied voltage and other parameters in metal-semiconductor- metal photodetectors(MSM-PD) is calcalated.It is shown that there exits a minimun transist time in MSM-PD as a result of nonlinear relationship between electron velocity and the electric field in GaAs.It is one of the best values ob- tained for MSM-PD whose electrode space is 3.0μm with the doping concentra- tion of 1×10^(14)cm^(-3)and the best working point of 2V_(FB).The results obtained are encouraging and can be used for designing GaAs MSM-PD with high speed re- sponse and modelling its response.