GaN-Based MSM Photodetectors Prepared on Patterned Sapphire Substrates

GaN-based metal-semiconductor-metal ultraviolet photodetectors (PDs) prepared on a patterned sapphire substrate (PSS) and a conventional flat sapphire substrate were both fabricated and characterized. It was found that we can reduce dark leakage current and enhance by about two orders of magnitude by using a PSS. The internal gain of the PDs prepared on a PSS was also much smaller.