GaN thin films via pulsed laser deposition with ZnO buffer layer by hydrothermal method

Gallium nitride (002) via pulsed laser deposition (PLD) is manufactured on sapphire substrate and hydrothermal-grown ZnO on sapphire. The film was deposited through the 248nm pulsed laser at 5×10- 3 torr nitrogen atmosphere. Temperature was controlled at 800 °C. The morphology of ZnO buffer layer and GaN films was examined using SEM and the crystallinity of the films was examined by XRD. In contrast to GaN grown on sapphire without any buffer layer, the one grown with ZnO buffer layer has better crystallinity due to the low lattice mismatch of ZnO and GaN. The FWHM of the GaN on ZnO XRD pattern was 0.3758°.