Thick GaN layer grown by Ga vapor transport technique

Using a novel Ga vapor transport technique, thick gallium nitride layers have been deposited on a 3-6 μm GaN film grown on sapphire substrate via hydride vapor phase epitaxy (HVPE). GaN powder was successfully used as a stable Ga source material for the growth. A growth rate of greater than 200 μm/hr was achieved by optimizing the growth temperature and the reactant gas flow rates. This growth rate is as high as that achieved by HVPE. The GaN layers were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AFM).