Influence of deposition temperature on the structural and dispersion parameters of TiO2 thin films

Abstract

Polycrystalline TiO2 thin films were deposited onto quartz substrates using RF magnetron sputtering technique at different substrate temperatures (573 K, 623 K, 673 K, and 773 K). X-ray diffraction (XRD) measurements revealed the isolation of anatase phase with (101) preferred crystal orientation for the film deposited at 773 K. Moreover, the topographical features of this film clarified the smoothness of the deposited films, with root mean square roughness (RMS) of 0.5 nm. The optical properties of the as-prepared thin films at different deposition temperatures was enlightened through structural correlation. Most of the films were transparent with transmittance intensity extending from 50 to 90% within the visible range. Due to the smoothness of the deposited films, the transmittance and reflectance spectra exhibited an oscillatory behavior. Additionally, from single effective oscillator model, the dispersion parameters were estimated. For the deposited films, the single oscillator energy (Eo), dispersion energy (Ed), lattice dielectric constant (eL), and infinite permittivity (e∞) extended in the range (3.42 ~ 3.99), (9.83 ~ 24.12), (4.39 ~ 7.75), and (3.88 ~ 7.04), respectively.