Si-based mid-infrared photodetector with dynamic Schottky barrier height modulation applicable for synchronous detection

Abstract

We have proposed an electrical shutter operation of a nano-antenna infrared photodetector using Schottky barrier height (SBH) modulation, where the SBH is modulated by a reverse bias voltage V b applied to the detector. The inhomogeneity of the Schottky junction may be dominant in the mechanism of barrier height reduction. Compared to the photocurrent i ph obtained by modulating the frequency of on–off of the incident light, the proposed method yields almost the same value. Therefore, it can be concluded that the proposed method is capable of synchronous detection measurement. In addition, since the proposed method does not require a mechanical shutter, it is a compact system that can be used in very small electrical equipment.