The effect of an annealing process on atomic layer deposited TiO 2 thin films

Abstract In this paper, we study the property changes in TiO 2 thin films related to annealing under various conditions. XPS analysis showed that the concentration of oxygen vacancies in TiO 2 thin films was reduced by annealing. In the case of annealing in an O 2 and air atmosphere, the oxygen vacancy concentration was reduced to the greatest extent as oxygen diffused into the TiO 2 thin film and rearrangement of atoms occurred. XRD analysis showed that the anatase structure of annealed TiO 2 thin films was clearly present compared to the as-deposited TiO 2 thin film. I–V analysis showed that the lower the concentration of oxygen vacancy, the lower the leakage current (O 2 annealed TiO 2 : 10 −4 A cm −2 ) than as dep TiO 2 thin film (∼10 −1 A cm −2 ). The dielectric constant of annealed TiO 2 thin films was 26–30 which was higher than the as-deposited TiO 2 thin film ( k ∼ 18) because the anatase structure became more apparent.