Microstructural evolution and optical properties of doped TiO2 films prepared by RF magnetron sputtering

In this study, Y2O3 and Nb2O5 doped titanium dioxide (TiO2) films on glass substrate were prepared using RF magnetron sputtering. The effects of dopants on the microstrucutral evolution and optical properties of TiO2 films were investigated. The as-deposited films are amorphous, irrespective of films containing Nb2O5 or Y2O3. After annealing at 400 °C and above in pure oxygen, anatase phase was obtained for pure TiO2 and Nb2O5 doped TiO2 films. Y2O3 dopant retards the crystallization to a higher temperature. After annealing, the transmittance of the TiO2 film is increased by Nb2O5 or Y2O3 addition. The higher transmittance of the doped samples can be correlated with their surface roughness.