Growth of high quality rutile TiO2 thin film using ZnO buffer layer on Si(100) substrate

The TiO2 rutile thin films were grown on Si(100) substrates with ZnO buffer layer at a substrate temperature of 500 °C by radio frequency (rf) magnetron sputtering. In order to investigate the effect of buffer layer thickness on the growth of the TiO2 film, the ZnO buffer layers were deposited in the thickness range of 70–150 nm. The thickness of the TiO2 films was about 200 nm identical for all the samples. The crystal structure of the buffer layers and the TiO2 thin films was characterized by X-ray diffractometer (XRD). The XRD spectra confirmed that TiO2 rutile film with high crystalline quality was achieved on the ZnO buffer layer, which had a great relation to the improvement of the crystalline quality of the ZnO buffer layer. The surface morphologies of the TiO2 rutile thin films were evaluated by atomic force microscopy (AFM). The roughness of the TiO2 thin films became smoother as the thickness of the ZnO buffer layer increased.