Investigation and Fabrication of p-Si/N-Mg0.3Zn0.7O:In Self-powered Heterojunction Photodiodes by Mist Atmospheric Pressure Chemical Vapor Deposition

In this study, the N-Mg0.3Zn0.7O:In thin films with 1% and 5% In doping concentration are deposited on the p-type Si substrate using mist atmospheric pressure chemical vapor deposition to form p-Si/N-Mg0.3Zn0.7O:In heterojunction. X-ray diffraction and X-ray photoelectron spectroscopy are used to estimate how In doping concentration affects the crystallinity and oxygen deficiency in the Mg0.3Zn0.7O:In thin films. The electrical and photoresponse characteristics of p-Si/N-Mg0.3Zn0.7O:In heterojunction photodiodes with 1% and 5% In doping in N-Mg0.3Zn0.7O:In are investigated. The photodiode with 5% In doping improves the responsivity, but the response time, rejection ratio, and specific detectivity are inferior to that with 1% In-doping. Moreover, the present p-Si/N-Mg0.3Zn0.7O:In heterojunction photodiodes are operated as self-powered photodiodes since the built-in potential is formed at the p-Si/N- Mg0.3Zn0.7O:In junction.