A Study on the Atomic Topography of Nanostructured TiO 2 Thin Films: Effect of Annealing

Titanium dioxide (TiO 2 ) is one of the most investigated metal oxides due to the wide range of applications such as photocatalysts. Photocatalytic activity will increased when the surface area is higher. Hence, this research focus on the surface topography and roughness of nanostructured TiO 2 films characterized by atomic force microscopy (AFM) in order to obtain thin films with the optimum roughness for photocatalytic activity. TiO 2 thin films were prepared by spin coating method at room temperature. The TiO 2 solutions of 0.1–0.2 M were synthesized from titanium butoxide in ethanol. TiO 2 films were deposited on the silicon substrates and annealed at 450°C. The results shown when the film was annealed, the grain were clearly observed. The grain size and the roughness increased when the film were annealed at high temperature. 0.2 M of TiO 2 thin film exhibit the higher roughness with Ra and RMS values were 51.29 and 78.90 nm, respectively.