Atomic layer deposition for rutile structure TiO 2 thin films using a SnO 2 seed layer and low temperature heat treatment

We study the rutile-TiO 2 film deposition with a high- k value using a SnO 2 seed layer and a low temperature heat treatment. Generally, heat treatment over 600 °C is required to obtain the rutile-TiO 2 film. However, By using a SnO 2 seed layer, we obtained rutile-TiO 2 films with heat treatments as low as 400 °C. The XPS analysis confirms that the SnO 2 and TiO 2 film were deposited. The XRD analysis showed that a heat treatment at 400 °C after depositing the SnO 2 and TiO 2 films was effective in obtaining the rutile-TiO 2 film when the SnO 2 film was thicker than 10 nm. The TEM/EDX analysis show that no diffusion in the thin film between TiO 2 and SnO 2 . The dielectric constant of the TiO 2 film deposited on the SnO 2 film (20 nm) was 67, which was more than twice as high as anatase TiO 2 dielectric constant (Anatase TiO 2 dielectric constant : 15–40). The current density was 10 −4 A cm −2 at 0.7 V and this value confirmed that the leakage current was not affected by the SnO 2 seed layer.