Effect of RF deposition power on the properties of Al-doped TiO 2 thin films

Abstract

The Al-doped TiO 2 (TiO 2:Al) films were deposited by simultaneous RF (Radio Frequency) magnetron sputtering of TiO 2 and DC (Direct Current) magnetron sputtering of Al. The advantage of this method is that the Al content could be independently controlled. TiO was more favorable to form and the deposited films became nonstoichiometric by increasing RF power density. The morphologies of TiO 2 and TiO 2:Al films were significantly affected by RF power density. The nonlinear refractive index of TiO 2:Al film on the glass substrate was measured by Moiré deflectometry, and was of the order of 10 − 8 cm 2 W − 1 . Compared with TiO 2 film, TiO 2:Al film had smaller grain size, lower porosity, higher linear refractive index, lower stress-optical coefficient and higher VIS-IR transmission.