Optical and Structural Properties of Nb:TiO2 Thin Films Deposited by DC Magnetron Sputtering at Ambient Temperature

Abstract

Article history: Received 22 April 2019 Accepted 27 May 2019 Available online 12 June 2019 This work reports on the influence of niobium on the structural and optical properties of titanium dioxide thin films made by DC Magnetron sputtering. The films were deposited on glass substrates at ambient temperature which stood at below 50 °C in the deposition chamber. Film thickness based on profilometry ranged from 432 nm to 620 nm. Parameters investigated among others include structure, optical constants, grain size and film density. The as-deposited films were found to be amorphous and turn to crystalline upon annealing in air. The film density increased with doping to a maximum estimated to be 5.77 at. % Nb, beyond which a decrease was recorded. It was also observed that the refractive index of the film increased with doping.