SiO2-TiO2 multilayer via electrochemical deposition: characterization of reflection and refractive index

The deposition of silica and titania films by electro-assisted technique, with the objective to obtain a multilayer structure, was studied. Tetraethyl orthosilicate/methyl triethoxysilane (TEOS/MTES) mixture and titanium(IV) isopropoxide (TTIP) were used as precursors. The films were deposited on both bare stainless steel and indium tin oxide (ITO) substrates and a total thickness of about 550nm was obtained for the four-layer structure. No heat treatment was performed before optical characterizations.Optical characterization was performed by ellipsometry on the single layers and on the multilayer coatings. The refractive index of silica and titania single layer, deposited on different substrates by electro-assisted technique and conventional dip coating, was measured in order to elucidate the influence of the substrates and deposition technique on the densification of the coatings. Moreover, the reflectance of the multilayer structure was also measured to demonstrate the possible use of the multilayer systems as Bragg reflector. [GRAPHICS] HighlightsSiO(2)-TiO2 multilayer deposition via electrochemistry without heat treatment.Characterization of refractive index of SiO2 and TiO2 single layers on different substrates.Thin films intercalation of low and high refractive index was obtained.A multilayer system as Bragg reflector was developed.