Abstract: ZnO thin films were deposited on TiO2 buffer layers by electron beam evaporation.The effect of annealing temperature on crystalline quality and photoluminescence of the films was studied.The structural characteristics of the as-deposited and annealed films were investigated by an X-ray diffractometer and a scanning probe microscope.The photoluminescence was studied by fluorophotometer.The analysis results show that all the annealed ZnO thin films grown on TiO2 buffer layers are preferentially oriented along the c-axis.The film annealed at 600℃ has the highest (002) diffraction peak,the strongest ultraviolet emission,and the weakest visible emission.Its grain sizes are uniform and its grains are closed packed.The samples annealed at 500 and 700℃ have relatively strong visible emissions that originated from defects.These indicate that the film annealed at 600℃ has the best crystalline quality.

Key words: ZnO thin film, TiO2 buffer layer, crystalline quality, photoluminescence