Thickness dependent physical and optical properties of SILAR deposited titania films

Abstract

Uniform and crystalline titanium dioxide (TiO2) thin films were obtained using Successive Ionic Layer Adsorption and Reaction (SILAR) technique. Films having varied thicknesses over a range from 700 nm to 1000 nm are deposited on glass substrate. Further TiO2 films were annealed at 673 K for 2 h. X-ray diffraction measurements of both annealed and as deposited films were done to analyze the effect of temperature. Crystallite size and micro strain of the TiO2 films were calculated to study their trend with different thicknesses of the film. Morphological and compositional characteristics are studied by Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Analysis (EDX) respectively. Images showed formation of uniform film without discontinuities on the base substrate. Optical constants of the films are figured out using UV–vis spectrophotometry. Absorbance spectra showed that as the thickness of the films increased absorbance of the films also increased. Direct and indirect bandgap values of TiO2 films was found using Tauc’s plot.