Structural evolution of amorphous thin films of titanium dioxide

In this paper, thin films TiO₂ were prepared by magnetron sputtering through deposition of metal Ti on Si substrates and subsequent gas-solid state reaction. Structural evolution of the thin film TiO₂ has been investigated from room temperature to 500 °C. Amorphous TiO₂ and its local crystallization in the thin films were observed by X-ray diffraction and transmission electron microscope (TEM). X-ray reflectivity experiments indicate that the expansion ratio of the thickness is 1.4 after oxidation at the temperature 300 °C. Dielectric constant of the amorphous TiO₂ thin film is about 18 at room temperature. The formation mechanism of the oxide thin films is also discussed.