Atomic layer deposition for rutile structure TiO2 thin films using a SnO2 seed layer and low temperature heat treatment

We study the rutile-TiO2film deposition with a high-kvalue using a SnO2seed layer and a low temperature heat treatment. Generally, heat treatment over 600 °C is required to obtain the rutile-TiO2film. However, By using a SnO2seed layer, we obtained rutile-TiO2films with heat treatments as low as 400 °C. The XPS analysis confirms that the SnO2and TiO2film were deposited. The XRD analysis showed that a heat treatment at 400 °C after depositing the SnO2and TiO2films was effective in obtaining the rutile-TiO2film when the SnO2film was thicker than 10 nm. The TEM/EDX analysis show that no diffusion in the thin film between TiO2and SnO2. The dielectric constant of the TiO2film deposited on the SnO2film (20 nm) was 67, which was more than twice as high as anatase TiO2dielectric constant (Anatase TiO2dielectric constant : 15-40). The current density was 10-4A cm-2at 0.7 V and this value confirmed that the leakage current was not affected by the SnO2seed layer.