UV photodetector based on graphene-GaN Schottky junction in MESFET

Abstract

We propose a graphene-gated GaN MESFET (Metal-Semiconductor Field Effect Transistor) and model the graphene-GaN Schottky junction for use as a UV (Ultra-violet) photodetector. The simulation results reveal a maximum device photoresponsivity of 0.167 A/W (EQE (External Quantum Efficiency) of 59.3%), a photocurrent gain of 5.31, a large bandwidth (in the THz range) and low power dissipation under 350 nm illumination at a reverse bias of 1.1 V. The results also demonstrate better or comparable performance to many Schottky-based photodiodes reported in the review. The device will prove useful for UV applications.