Condensation and densification mechanism of sol-gel TiO2 layers at low temperature

Titanium dioxide films were prepared by the sol-gel process at low temperat ure under dry and humid conditions. The effect of solution parameters on th e solution reactivity was studied. Layers deposited on silicon wafers as we ll as on organic substrates were characterized by Fourier Transform infrare d spectoscopy and ellipsometry. Their mechanical quality was also tested. R esults reported in this paper demonstrate the influence of the temperature and humidity during post-deposition treatment on the network development an d densification. A suitable balance between both mechanisms led to hard and flexible coatings compatible with the thermal expansion of polymer substra tes.