Continuous Tunable Energy Band Tailoring Boosts Extending the Sensing of the Waveband Based on (In_xGa_1–x)₂O₃ Solar-Blind Photodetectors

Abstract

Rising wide bandgap semiconductor gallium oxide (Ga 2 O 3 ) displays huge potential in performing solar-blind photodetection, with constraint in narrow detection wavebands in nature, whereas bandgap modulation through the introduction of exotic atoms into Ga 2 O 3 has an essential effect on the tunable performance of photodetectors and the detection waveband. Here, a novel method for the preparation of (In x Ga 1−x ) 2 O 3 alloy films is proposed, and the continuous tuning of the bandgap in the range of 3.70−4.99 eV is achieved by varying the In-doping content. Alloy-based metal−semiconductor−metal photodetectors were fabricated, achieving a peak responsivity between 254 and 295 nm, superior performance compared to Ga 2 O 3 photodetectors, with a photo-to-dark current ratio as high as 10 6 , and a better optical image-sensing capability. This study offers new insight for high-performance detection of full solar-blind waveband ultraviolet light.