Nitride-Based Metal–Semiconductor–Metal Photodetectors with InN/GaN Multiple Nucleation Layers

Abstract

GaN metal–semiconductor–metal (MSM) photodetectors with InN/GaN multiple nucleation layers were proposed and fabricated. We achieved a much smaller dark current and a larger photocurrent-to-dark current ratio from the proposed device with InN/GaN multiple nucleation layers than that from the GaN MSM photodetector with conventional single low-temperature GaN nucleation layer. We also achieved a much larger UV-to-visible spectral response ratio of photoresponse at 360–450 nm from the photodetector with InN/GaN multiple nucleation layers. Furthermore, we also found that we can significantly reduce noise current density using these InN/GaN multiple nucleation layers.