MgZnO-Based Schottky Barrier Ultraviolet-B Photodiode by Ultrasonic Spray Pyrolysis Deposition

This article demonstrates a Mg0.4Zn0.6 O-based ultraviolet-B photodiode using ultrasonic spray pyrolysis deposition (USPD). The material characteristics of the USPD-deposited Mg0.4Zn0.6O thin film are investigated by the X-ray diffraction, X-ray photoelectron spectroscopy, photoluminescence, and ellipsometer. Schottky photodiode is fabricated by using Pt as the anode and Ti/Au as the cathode. Note that 0.84-eV Schottky barrier height is formed between Pt and Mg0.4Zn0.6O. The present Schottky barrier photodiode shows high rectification ratio of 104 and high ultraviolet-to-visible rejection ratio of ${1.83} \times {10}^{{5}}$ . Furthermore, the specific detectivity is over 1011 Jones at ultraviolet-B region.