InGaN/GaN multiple-quantum well (MQW) structure was epitaxial growth by metal-organic chemical vapor deposition (MOCVD). Their MIS photodiodes with SiO2 interlayer were fabricated successfully using photochemical vapor deposition. The normal undoped-GaN metal-semiconductor-metal (MSM) potodiodes were also prepared to compare with them. It was found that the minimum dark current of InGaN/GaN MQW photodiodes was 4.2 × 10 -13 A with 88nm-thick SiO2 layer under 5 V reverse bias voltage. Furthermore, it was found that we can significantly reduce the dark current of this photodiodes by inserting a thin SiO2 interlayer in between metal electrode and the underneath InGaN/GaN MQW. With a 53 nm-thick SiO2 interlayer, it was also found that we could achieve a high 1.53 × 103 photo current to dark current contrast.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)