InGaN Metal–Semiconductor–Metal Photodiodes with Nanostructures

Abstract

InGaN self-assembled nanostructures have been prepared by growth interruption during metal-organic chemical vapor deposition (MOCVD) growth. With a 12 s growth interruption, we successfully formed InGaN nanostructures with a typical lateral size of 25 nm and an average height of 4.1 nm. The nanostructure density was approximately 2×1010 cm-2. In contrast, much larger InGaN nanostructures were obtained without growth interruption. InGaN metal-semiconductor-metal (MSM) photodiodes with and without nanostructures were also fabricated. Although the dark currents were approximately the same for all detectors, we could achieve a much larger photocurrent-to-dark current contrast ratio from samples with small self-assembled InGaN nanostructures.