Systematic Comparison of Thermal Annealing and Laser Treatment of TiO2 Thin Films Prepared by Sol-Gel Processing

Thin films with titania composition were prepared on glass substrates by dip-coating from coating solutions based on soluble precursor powders. The as-dried deposits were thermally annealed in a furnace and irradiated by a CO2 laser, respectively. Oven temperature can systematically be correlated to laser power density in terms of film thickness and refractive index. Results indicate that the formation of anatase and rutile critically depends on the different treatment conditions. Some specific microstructural features that originate from the laser irradiation are highlighted.