Anatase-type TiO₂ thin films produced by lattice deformation

TiO₂ thin films were grown onto SrTiO₃ substrates by a molecular beam epitaxy (MBE) method using an oxygen radical source. The structure of the thin films obtained was evaluated by X-ray reflection diffractometer (XRD) and reflection high energy electron diffraction (RHEED); TiO₂ thin films were determined to be of anatase type and were epitaxially grown in the direction of the c-axis, parallel to the [001] of the substrates. Near the interface, the a-value of thin films increased and the c-value shrank in comparison to that of anatase powder. These results indicated that the anatase phase of TiO₂ was induced by a lattice matching process at the interface between SrTiO₃ and TiO₂.