Ga2O3 films grown on sapphire by the thermal evaporation of GaN powders

We have prepared the gallium oxide (Ga2O3) films on sapphire substrates by a thermal evaporation of GaN powders. We have characterized the films by using the x-ray diffraction (XRD), scanning electron microscopy (SEM), and the photoluminescence (PL). SEM and XRD revealed that the deposits were Ga2O3 thin films with monoclinic structure. PL spectrum of Ga2O3 films under excitation at 325 nm showed a blue emission.