LAUSR

Abstract TiO2 films were deposited by DC pulsed magnetron sputtering with different sputtering power density (SPD). Then, as-deposited TiO2 films were annealed at 600 °C and the anatase TiO2 films were obtained. XPS results showed Ti/O atom ratio was kept at 1/(1.94 ± 0.04) for all as-deposited and annealed TiO2 films. XRD results showed that the annealed TiO2 films displayed obvious anatase (001) preferred orientation, which was deposited with SPD in 0.83 W/cm2. The cross-section TEM results showed that annealed TiO2 film with anatase (001) preferred orientation consisted of a small quantity of columnar crystals and a majority of equiaxed crystals, which [001] crystallographic axis was parallel to the normal direction of film. AFM results revealed that with SPD in 0.83 W/cm2, the dominated diffusion effect controlled TiO2 film growth process with Volmer-Weber mode, which contained the nano-size anatase crystal nuclei. The [001] crystal orientation of anatase crystal nuclei was uniform parallel to the normal direction of TiO2 film growth surface. During the annealing process, the nano-size anatase crystal nuclei grew and coalesced into the large anatase grains without the change of [001] crystal orientation, which resulted in TiO2 film with obvious (001) preferred orientation.