Single <i>β</i>-Ga<sub>2</sub>O<sub>3</sub> microbelt solar-blind photodetector with high specific detectivity, high rejection ratio and fast speed
Zhiyao Zheng, Kewei Liu, Zhen Cheng, Baoshi Qiao, Xing Chen, Chang Zhou, Jialin Yang, Qiu Ai, Yongxue Zhu, Binghui Li, Lei Liu, Dezhen Shen
Abstract
Abstract An ideal solar-blind photodetector should possess high responsivity, low dark current, high speed, high spectral selectivity, high stability and a facile fabrication method. In this work, a high-quality single β -Ga 2 O 3 microbelt photodetector is fabricated through low-pressure chemical vapor deposition and in situ atmospheric pressure annealing techniques. Due to the high quality and low defect density, this device shows a peak responsivity of 9.47 A W −1 at 256 nm, a dark current of 1 pA and an ultrashort fall time of 1.37 μ s under 20 V bias. Moreover, an ultrahigh specific detectivity of ∼10 14 Jones and an extremely large solar-blind/ultraviolet A rejection ratio of nearly 10 5 have also been achieved, suggesting the excellent sensitivity and wavelength selectivity of our single β -Ga 2 O 3 microbelt photodetector. Besides that, the β -Ga 2 O 3 microbelt photodetector exhibits excellent mechanical and long-term stabilities. Our findings provide a facile and promising route to develop high performance solar-blind UV photodetectors.