Investigation of the crystalline quality of a gallium oxide thick film grown by RF magnetron sputtering

Crystalline quality and optical properties of gallium oxide films grown on SiO2substrates by RF magnetron sputtering were studied. After the post annealing, it could be confirmed growth of gallium oxide (Ga2O3) film changed in a β ‐Ga2O3 film. Estimated optical energy gap of as‐grown and post annealed films are the same from 4.85 to 4.90 eV. The energy gap for as‐deposited film corresponds to band gap of β ‐Ga2O3.It has a property of β ‐Ga2O3 nevertheless the as‐deposited Ga2O3 films. The integrated absorption coefficient under the energy gap decreases with increasing thickness of Ga2O3 film. These results indicate that crystalline quality of β ‐Ga2O3 film is improved by increment the film thickness. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)