In-situ fabrication of PtSe2/GaN heterojunction for self-powered deep ultraviolet photodetector with ultrahigh current on/off ratio and detectivity
PtSe2, heterojunction, deep ultraviolet, photodetectors, self-powered
The research of ultraviolet photodetectors (UV PDs) have been attracting extensive attention, due to their important applications in many areas. In this study, PtSe2/GaN heterojunction is in-situ fabricated by synthesis of large-area vertically standing two-dimensional (2D) PtSe2 film on n-GaN substrate. The PtSe2/GaN heterojunction device demonstrates excellent photoresponse properties under illumination by deep UV light of 265 nm at zero bias voltage. Further analysis reveals that a high responsivity of 193 mA·W–1, an ultrahigh specific detectivity of 3.8 × 1014 Jones, linear dynamic range of 155 dB and current on/off ratio of ~ 108, as well as fast response speeds of 45/102 μs were obtained at zero bias voltage. Moreover, this device response quickly to the pulse laser of 266 nm with a rise time of 172 ns. Such high-performance PtSe2/GaN heterojunction UV PD demonstrated in this work is far superior to previously reported results, suggesting that it has great potential for deep UV detection.
Tsinghua University Press
Ranran Zhuo,Longhui Zeng,Huiyu Yuan,Di Wu,Yuange Wang,Zhifeng Shi,Tingting Xu,Yongtao Tian,Xinjian Li,Yuen Hong Tsang, In-situ fabrication of PtSe2/GaN heterojunction for self-powered deep ultraviolet photodetector with ultrahigh current on/off ratio and detectivity. NanoRes.2019, 12(1): 183–189