Single-phase gamma-LiAlO2 layer with a preferred (100) orientation on (0001) sapphire substrate is successfully fabricated by vapor transport equilibration (VTE) technique. The VTE-treated surface of (0001) sapphire is polycrystalline shown to be a single-phase of gamma-LiAlO2 at low VTE temperature (750-900degreesC), and becomes highly oriented in [100] direction at proper VTE temperature of similar to1100degreesC. The transparence of the obtained gamma-LiAlO2// sapphire(0001) is greatly enhanced as the gamma-LiAlO2 layer becomes oriented. These results reveal the possibility of fabricating gamma-LiAlO2 (100)//sapphire(0001) composite substrate by VTE for M-plane GaN-based epitaxial film. (C) 2004 Elsevier B.V. All rights reserved.