On the response of gamma irradiation on atomic layer deposition-grown beta-Ga2O3 films and Au-beta-Ga2O3-Au deep ultraviolet solar-blind photodetectors

Abstract

beta -Ga2O3 films are deposited on (0001) sapphire substrates using triethylgallium (TEGa) and nitrous oxide (N2O) under high N2O/TEGa ratios by atomic layer deposition (ALD). Au-beta -Ga2O3-Au metal/semiconductor/metal (MSM) solar-blind deep ultraviolet (DUV) photodetectors (PDs) are prepared using Au interdigitated electrodes deposited by thermal evaporation. The ALD-grown beta -Ga2O3 films and Au-beta -Ga2O3-Au DUV MSM PDs are irradiated with gamma ray to explore the response of gamma irradiation on the beta -Ga2O3 films and beta -Ga2O3 DUV MSM PDs. It is found that gamma irradiation tends to deteriorate the structural properties of the beta -Ga2O3 films and dark current of the beta -Ga2O3 DUV MSM PDs. Nevertheless, it also results in an increase in the 254nm illuminated photocurrent of the Au-beta -Ga2O3-Au DUV MSM PD. Energy band diagram schematics of the biased Au-beta -Ga2O3-Au DUV MSM PDs are presented to interpret the influence of gamma irradiation-induced defects on the performances of the Au-beta -Ga2O3-Au DUV MSM PDs.