Study on Preparation and Optical Absorption of Ge Doped TiO2 Composite Thin Films by Sol-Gel Method

By using the sol-gel method, TiO2 thin films and Ge doped TiO2 composite thin films were fabricated onto quartz substrates. XRD, XPS and UV-vis were used to characterize the phase structure, the atomic chemical states and optical absorption of these composite TiO2 thin films. XRD results indicate that diffraction peak of anatase is observed in samples. XPS result reveals that there is Ge crystal in Ge doped films which were prepared by sol-gel method, and Ge exists as elemental Ge and GeO2 in the films. The composite TiO2 thin films by sol-gel method exhibits the absorption shift to visible region due to Ge doped TiO2 thin films.