最小标准模型(MSM)结构的光电探测器主要分为光导型和肖特基型两种。制备得到了肖特基型的氮化镓(GaN) MSM结构紫外光电探测器,采用这种结构的器件主要是因为其暗电流低、响应时间快、响应度大、寄生电容小等优点。MSM形状的叉指电极是通过传统的紫外光刻和湿法刻蚀得到的,并采用Au作为金属电极。得到的肖特基型GaN紫外光电探测器的暗电流在1 V偏压下为3.5 nA,器件在1 V偏压下的最大响应度值出现在362 nm处,大小为0.12 A/W,器件的上升时间小于10 ns,下降时间为210 ns。并对器件响应时间的影响因素进行了深入的分析。

The minimum standard model (MSM) structured photodetectors includes photoconductive type and Schottky type. Schottky GaN MSM photodetectors have been made due to its excellent properties of low dark current,high speed,large responsivity,small parasitic capacitance. MSM structured electrodes were fabricated by using conventional ultraviolet (UV) lithography and wet etching,and Au were used as the metal electrodes. The dark current of the fabricated Schottky GaN UV photodetectors was 3.5 nA at 1 V bias voltage. The maximum responsivity of the device was 0.12 A/W at 362 nm under 1 V bias voltage. The rise time of the device was no more than 10 ns,and the fall time was 210 ns. The influencing factor of the response time has been investigated deeply.