Properties of TiO2‐based transparent conducting oxides

The development and properties of titanium dioxide (TiO 2 )-based transparent conducting oxides (TCO), which exhibit properties comparable to those of In 2-x Sn x O 3 (ITO), are reviewed in this article. An epitaxial thin film of anatase Ti 0.94 Nb 0.06 O 2 exhibited a resistivity (p) of 2.3 x 10 -4 Ω cm and internal transmittance of ~95% in the visible light region. Furthermore, we prepared polycrystalline films with p of 6.4 x 10 -4 Ω cm at room temperature on glass substrates by using sputtering. We focus on characteristics unique to TiO 2 -based TCO, such as a high refractive index, high transmittance in infrared, and high stability in reducing atmospheres. Possible applications of TiO 2 -based TCOs, as well as the mechanism of the transparent conducting properties found in this d-electron-based TCO, are discussed in this review.

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