Using a novel gallium (Ga) vapor transport technique, thick gallium nitride (GaN) layers have been grown using GaN powder as the source material. In this technique, GaN powder decomposes at 1100°C into gallium and nitrogen vapors. The Ga vapors are transported to the seed substrate and reacted with ammonia to form a crystalline GaN layer. The seed was composed of a sapphire substrate with a 2 microns HVPE GaN layer on it. The growth temperature was set at 1180°C. Using this technique, growth rates as high as 500 μm/hr were achieved. The grown GaN layers were single crystal and were characterized by X-ray diffraction and scanning electron microscopy.