Fabrication of β-Ga_2O_3 thin films and solar-blind photodetectors by laser MBE technology

Abstract

Laser molecular beam epitaxy technology has been employed to deposit β-gallium oxide (β-Ga2O3) on (0001) sapphire substrates. After optimizing the growth parameters, (2¯01)-oriented β-Ga2O3 thin film was obtained. Ultraviolet-visible absorption spectrum demonstrates that the prepared β-Ga2O3 thin film shows excellent solar-blind ultraviolet (UV) characteristic with a band gap of 5.02 eV. A prototype photodetector device with a metal-semiconductor-metal structure has been fabricated using high quality β-Ga2O3 film. The device exhibits obvious photoresponse under 254 nm UV light irradiation, suggesting a potential application in solar-blind photodetectors.