Structural and Optical Property of High Quality GaN Thin Film on Si with ZnO Buffer Layer

Abstract

A method was applied to improve the crystallization quality of GaN. ZnO thin films were deposited on n-Si (111) at 600°C by pulsed laser deposition (PLD), and GaN thin films were grown on Si or ZnO/ Si by R. F. magnetron sputtering system. Several GaN films were prepared with ZnO as buffer layer without annealing, with ZnO as buffer layer annealed at 850°C, 900°C and 950°C and with no buffer layer annealed at 950°C, respectively. The crystallization, optical property and morphology of all GaN films prepared were studied by X-ray diffraction (XRD), Fourier transform infrared spectrophotometer (FTIR), photoluminescence (PL) and scanning electron microscope (SEM). The results show that ZnO buffer layer plays an important role in improving the crystallization quality of GaN.