Synthesis and properties of ZnO films with (1 0 0) orientation by SS-CVD

ZnO films with (1 0 0) preferred orientation have been synthesized on Si (1 0 0) and α-Al2O3 (0 0 0 1) substrates by single-source chemical vapor deposition (SS-CVD) using zinc acetate dihydrate (solid) as a precursor. X-ray diffraction (XRD) reveals that a lower growth temperature and a higher deposition rate will facilitate the forming of (1 0 0) orientation. X-ray photoelectron spectroscopy (XPS) indicates that the O 1s peak in the surface of films can be consistently fitted by two nearly Gaussian curves centered at 530.08 and 531.67 eV, respectively. Transmittance about 90% in visible region and near 100% absorption in UV region for (1 0 0) oriented ZnO films are confirmed by the optical transmission spectra, which are better than those of randomly oriented films. The optical band gap is evaluated to be around 3.31 eV for the (1 0 0) oriented ZnO.