Transparent conducting Nb-doped anatase TiO2 (TNO) thin films sputtered from various oxide targets

Transparent conducting Nb-doped anatase TiO2 (TNO) epitaxial films were sputtered from TiO2-, Ti2O3-, and Ti-based targets at various oxygen partial pressures (Po-2). Using the TiO2- and Ti2O3-based targets, highly conductive films showing a resistivity (rho) of similar to 3 x 10(-4) Omega cm could be formed without postdeposition treatment. In the case of the TNO films formed from the Ti-based target, reductive annealing had to be carried out at a temperature of 600 degrees C to achieve similar resistivity values. Thus, the use of oxide targets is preferable to obtain as-grown transparent conducting TNO films. In particular, the Ti2O3-based target is practically advantageous, because it offers a wide range of optimal Po-2 values at which p values of the order of 10(-4) Omega cm are achievable. (C) 2009 Elsevier B.V. All rights reserved.