High-temperature photocurrent mechanism of β -Ga2O3 based metal-semiconductor-metal solar-blind photodetectors

作者：B. R. Tak, Manjari Garg, Sheetal Dewan, Carlos G. Torres-Castanedo, Kuang-Hui Li, Vinay Gupta, Xiaohang Li, R. Singh · 发表于：Journal of Applied Physics · 年份：2019 · DOI：10.1063/1.5088532 · 被引用次数：129 · 研究领域：Ga2O3 and related materials、Advanced Photocatalysis Techniques、Thin-Film Transistor Technologies

High-temperature operation of metal–semiconductor–metal (MSM) UV photodetectors fabricated on pulsed laser deposited β-Ga2O3 thin films has been investigated. These photodetectors were operated up to 250 °C temperature under 255 nm illumination. The photo to dark current ratio of about 7100 was observed at room temperature and 2.3 at a high temperature of 250 °C with 10 V applied bias. A decline in photocurrent was observed until a temperature of 150 °C beyond which it increased with temperature up to 250 °C. The suppression of the UV and blue band was also observed in the normalized spectral response curve above 150 °C temperature. Temperature-dependent rise and decay times of temporal response were analyzed to understand the associated photocurrent mechanism at high temperatures. Electron–phonon interaction and self-trapped holes were found to influence the photoresponse in the devices. The obtained results are encouraging and significant for high-temperature applications of β-Ga2O3 MSM deep UV photodetectors.