A $\beta$-${\rm Ga}_{2} {\rm O} _{3}$/GaN Hetero-Structured Solar-Blind and Visible-Blind Dual-Band Photodetector

The authors report the fabrication of a β-Ga ₂ O ₃ /GaN solar-blind and visible-blind dual-band photodetector (PD). It was found that we could control the depletion depth of the device and thus switch the operation mode between solar-blind and visible-blind by simply changing the applied bias. It was also found that we could achieve a deep-UV to near-UV contrast ratio of 4.6 × 10 ³ when the device was biased at 1 V. Furthermore, it was found that near-UV to visible contrast ratio of the fabricated β-Ga ₂ O ₃ /GaN PD was 8.5 × 10 ² when biased at 10 V.