Development of solar-blind photodetectors based on Si-implanted beta-Ga2O3

Abstract

beta-Ga2O3 films grown on Al2O3 by a metalorganic chemical vapor deposition technique were used to fabricate a solar-blind photodetector with a planar photoconductor structure. The crystal structure and quality of the beta-Ga2O3 films were analyzed using X-ray diffraction and micro-Raman spectroscopy. Si ions were introduced into the beta-Ga2O3 thin films by ion implantation method and activated by an annealing process to form an Ohmic contact between the Ti/Au electrode and the beta-Ga2O3 film. The electrical conductivity of the beta-Ga2O3 films was greatly improved by the implantation and subsequent activation of the Si ions. The photoresponse properties of the photodetectors were investigated by analyzing the currentvoltage characteristics and the time-dependent photoresponse curves. The fabricated solar-blind photodetectors exhibited photoresponse to 254 nm wavelength, and blindness to 365 nm light, with a high spectral selectivity. (C)2015 Optical Society of America