Electrical Properties of Nb-Doped TiO2 Thin Films Deposited by Co-sputtering Process

Abstract

Nb-doped Ti thin films were fabricated by co-sputtering of TiO2 doped 6 at% by Nb2O5 and Nb targets. The anatase polycrystalline thin films were obtained by post-annealing at 350oC in vacuum atmosphere. The electrical properties of the films were determined by the Hall method using standard clove-leaf geometry. When the Nb concentration increased, the number of electron increased from 4×1018 cm-3 to 2.4×1020 cm-3, while the resistivity fell down from 10 to 3.5×10-3 Ωcm. It means that this co-sputtering process can be considered as a method to improve conducting properties of Nb:Ti thin films. With low resistivity and high optical transmittance (higher than 80% in the visible range), the fabricated thin films can be applicable for transparent electrodes or heat-resistant coating. Keywords: Nb-doped TiO2, co-sputtering method, transparent conducting