The growth of nonpolar a- plane (1 1 -2 0) orientation of the GaN epilayers were confirmed by high resolution x-ray diffraction studies. An in-plane orientation relationship was found to be [0 0 0 1] GaN || [-1 1 0 1] sapphire and [-1 1 0 0] GaN || [1 1 -2 0] sapphire. SEM image shows the reasonably smooth surface. The photoluminescence spectrum shows near band emission (NBE) at 3.439 eV. The room temperature I-V characteristics of Au/a-GaN schottky diode performed. The Schottky barrier height (φb) and the ideality factor (η) for the Au/a-GaN schottky diode found to be 0.50 eV and 2.01 respectively. © 2012 SPIE.