TiO 2 multilayer films were deposited by the sol-gel method on glass and SiO 2 /glass substrates. 10% of Cu was added to the coating solution, to study its effect on the amorphous to anatase phase transition, with a view to improving the photocatalytic activity. Densification of the films was obtained by thermal treatment at 500 o C for 1 hour in oxidative and reductive conditions. In order to check the correlation between the influence of copper, substrate and annealing temperatures on the structural, morphological and optical properties, the samples were characterized by FTIR, XPS, SEM and fractal analysis. Transformation of CuO from as-prepared samples into Cu 2 O and metallic Cu, depending on the treatment conditions, was shown. The composition and stoichiometry of the oxide films in the first atomic layers were quantitatively determined as chemical state relative concentrations.