Demonstration of zero bias responsivity in MBE grown β-Ga2O3 lateral deep-UV photodetector

Abstract

We demonstrate zero-bias spectral responsivity in MBE-grown β-Ga2O3 planar UV-C detector with good linearity up to optical power density of 4.6 mW cm−2. Devices with asymmetrical metal contacts were realized on 150 nm thick β-Ga2O3 films on sapphire. The device exhibited a spectral responsivity of 1.4 mA W−1 at 255 nm under zero-bias condition, dark current <10 nA at 15 V and UV-to-visible rejection ratio ∼105 at 5 V. The demonstrated UV-C detector exhibited an estimated high detectivity of 2.0 × 1012 Jones at 1 V and were found to be very stable and repeatable, suggesting its potential use for focal plane arrays.