Influence of preparation technique on the microscopic structure and surface morphology of nanometer TiO₂ thin films

Nanometer TiQ₂ thin films are prepared by a sol-gel method and the effects of preparation technique on the microstructure and surface morphology of the obtained materials are studied using X-ray Diffraction [XRD], IR spectrum [IR], UV-VIS spectrum [UV-VIS], AFM and X-ray photoelectron spectroscopy [XPS]. The results show that the TiO₂thin films are of anatase and rutile phase structures when annealed in a temperature range from 450°C to 600°C. When heated up to 700°C, the structure of TiO ₂ film changed into rutile completely. In the TiQ₂ thin films, there is some residual carbon from the starting organometallic components and a small amount of sodium ions diffused from the glass substrates. During heat-treatment, the absorption peak of water become weak gradually and the organic groups are disappeared completely at 500°C. Optimum film layers are obtained for the UV absorbance index. AFM result shows that the rough morphology of surface [RMS] of films is about 2-3nm or so.