Ta-doped anatase TiO2 epitaxial film as transparent conducting oxide

We present electrical transport and optical properties of Ta-doped TiO2 epitaxial thin films with varying Ta concentration grown by the pulsed laser deposition method. The Ti0.95Ta0.05O2 film exhibited a resistivity of 2.5 x 10(-4) Omega cm at room temperature, and an internal transmittance of 95% in the visible light region. These values are comparable to those of a Widely used transparent conducting oxide (TCO), indium tin oxide. Furthermore, this new material falls into a new category of TCOs that utilizes d electrons.