Growth and characterization of ZnO films on (0 0 1), (1 0 0) and (0 1 0) LiGaO2 substrates

ZnO films were fabricated on LiGaO2 (0 0 1), (1 0 0) and (0 1 0) planes by RF magnetron sputtering. The structural, morphological and optical properties of as-grown ZnO films were investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), Raman spectra and photoluminescence (PL) spectra. It is found that the orientation of ZnO films is strongly dependent on the substrate plane. [0 0 0 1], [1 1¯ 0 0] and [1 1 2¯ 0] oriented ZnO films are deposited on LiGaO2 (0 0 1), (1 0 0) and (0 1 0), respectively. AFM shows the (0 0 0 1) ZnO film consists of well-aligned regular hexagonal grains. Raman spectra reveal a tensile stress in the (0 0 0 1) ZnO film and a compressive stress in (1 1¯ 0 0) and (1 1 2¯ 0) ZnO films. PL spectra of all ZnO films exhibit only a near-band-edge UV emission peak.