The effect of substrate temperature on the properties of d.c. reactive magnetron sputtered titanium oxide films

Abstract

TiO x films are deposited on glass substrates (75 × 25 mm 2) by d.c. reactive magnetron sputtering from a pure 99.6% Ti disk. During the sputtering process, oxygen partial pressure and total pressure are 6 × 10 −2 PPa and 8 × 10 −1 Pa respectively. The substrate temperature varied from ambient to 500 °C. The results of X-ray diffraction show that all films have an anatase crystal structure. The film deposited at ambient temperature is textured with the (101) crystal direction normal to the substrate surface. With increase in the substrate temperature, the films tend to be randomly oriented. When the substrate temperature is a above 450 °C, the film again has a preferred orientation. However, the preferred orientation is not (101) but (004). With the variation in substrate temperature, the optical properties (refractive index, optical band gap and extinction coefficient) of TiO 2 films also change strongly. In this paper, these effects of substrate temperature on the films' properties are discussed.