Ga2O3 photodetector arrays for solar-blind imaging

Abstract

A photodetector array has been demonstrated comprising 4 × 4 metal–semiconductor–metal structured Ga₂O₃ photodetector cells. The photodetector cell exhibited a low dark current of 4.0 × 10⁻¹⁰ A, and its peak responsivity at 256 nm was about 1.2 A W⁻¹ when the bias was 10 V. The UV/visible rejection ratio was more than 4 orders of magnitude with a cut-off wavelength at 265 nm, which indicated that the photodetector had a high solar-blind wavelength selectivity. Due to the benefits of the high quality and uniformity of all the 16 photodetector cells, clear images were obtained by using the photodetector array as an imaging device, which is the first report on solar-blind imaging of Ga₂O₃ photodetector arrays. The results reported in this paper may provide a strategy to develop solar-blind imaging by integrating Ga₂O₃-based photodetectors into array configuration.