Nb doping effect on TiO2-x films for bolometer applications

Abstract

Nb-doped TiO2-x thin films were deposited using a 1 at% niobium doped titanium target by RF reactive magnetron sputtering at various oxygen partial pressures (pO(2)). The films appeared amorphous in the pO(2) range of 4.4-4.7% with resistivity ranging from 039 Omega cm to 2.48 Omega cm. Compared to pure TiO2-x films, the resistivity of the Nb-doped TiO2-x films did not change sensitively with the oxygen partial pressure, indicating that the resistivity of the films can be accurately controlled. 1/f noise parameter of Nb-doped TiO2-x films were found to decrease largely while the measured temperature coefficient of resistance (TCR) of the films was still high. The obtained results indicate that Nb-doped TiO2-x films have great potential as an alternative bolometric material. (C) 2016 Elsevier Ltd. All rights reserved