The influence of interface states and bulk carrier lifetime on the minority carrier behavior in an illuminated metal/insulator/GaN structure

Abstract

An influence of electronic states at an insulator/GaN interface on the behavior of excess holes in an ultraviolet-illuminated metal/ SiO 2/n-GaN structure has been studied by numerical simulations for weak (gate bias of −0.1 V ) and strong (−1 V ) depletion, in a wide range of excitation light intensities (from 10 10 to 10 20 photons cm −2 s −1) and for various bulk carrier lifetimes (from 1 to 100 ns). It has been found that the interface states with densities of 10 12 eV −1 cm −2 dramatically reduce the total (integrated in the whole GaN layer) density of photogenerated holes and thus degrade the sensitivity of the metal/insulator/GaN-based photodetector.