Thermal annealing of amorphous Ti-Si-O thin films

Ti-Si-O thin films were deposited using, an aerosol chemical vapor deposition process at atmospheric pressure. The film structure and microstructure were analyzed using several techniques before and after thermal annealing,. Diffraction results indicate that the films remain x-ray amorphous after annealing, whereas Fourier transform infrared spectroscopy gives evidence of a phase segregation between amorphous SiO2 and well-crystallized anatase TiO2. Crystallization of anatase TiO2 is also clearly shown in the Raman spectra. Transmission electron microscopy analysis indicates that anatase TiO2 nanograins are embedded in a SiO2 matrix in an alternated SiO2/TiO2 multilayer structure.