Sol-gel prepared β-Ga2O3 thin films for ultraviolet photodetectors

beta-Ga2O3 thin films have been prepared on (0001) sapphire substrates by the sol-gel method. X-ray diffraction showed that beta-Ga2O3 polycrystalline films were formed at heat-treatment temperatures above 600 degrees C. With increasing heat-treatment temperature above 900 degrees C, the lattice constants of the beta-Ga2O3 films decreased, while the band gap increased. Planar geometry photoconductive detectors based on the sol-gel prepared beta-Ga2O3 thin films have been fabricated. They showed the photoresponse only for the wavelengths shorter than 270 nm, which correspond to the solar-blind region. The peak wavelength in the spectral response depended on the heat-treatment temperature in the sol-gel process. (c) 2007 American Institute of Physics.