Comparison of non-polar ZnO (1 120) films deposited on single crystal ZnO (1 120) and sapphire (0112) substrates

摘要

Homo- and heteroepitaxial growth of non-polar Zinc oxide (ZnO) (1 12 0) films was achieved on single crystal ZnO (112 0) and sapphire (0 1 1 2) substrates by an atmospheric pressure metal-organic chemical vapor deposition (MOCVD) using zinc acetylacetonate and oxygen gas. The full-widths at half-maximum (FWHM) of X-ray diffraction patterns of grazing incident diffraction measurement of homoepitaxial ZnO films were smaller by one order of magnitude than those of heteroepitaxial ZnO films. A striped pattern along the c-axis of ZnO was clearly observed in homoepitaxial films deposited at 650 ℃. Room temperature photoluminescence spectra of homoepitaxial films exhibited only a strong near-band-edge emission. Free exciton emissions were clearly observed in the photoluminescence spectra of homoepitaxial ZnO films at 5 K.