The growth of GaN crystals was conducted by GaH-VPE method. In this method, GaHx was used as Ga source, which enables us to grow GaN crystals with high crystallinity. However, the growth rate was lower than 20um/h because of low GaHx supply. In this work, the structure for the synthesis of GaHx was optimized to increase the reaction efficiency between Ga and H_2 gas.
