A low-temperature and low-cost method to produce high-quality epitaxial anatase TiO2 thin films

Epitaxial anatase TiO2 thin films were successfully grown on lattice-matched SrTiO3 (001) substrates by a novel hydrothermal method at very low temperatures (120-200 degrees C). This method is extremely simple and inexpensive in that the SrTiO3 substrate itself provides the source material for the TiO2 film. X-ray diffraction confirmed the high crystallinity and phase purity of the anatase films. The epitaxial relationship between the film and the substrate was determined as (001)[100]anatase H (001)[100]SrTiO3. Atomic force microscopy revealed the average size of the anatase crystallites as approximately 50 to 200 nm.