“…In recent years, the sol-gel technique has been successfully applied to prepare functional ceramic and glass materials for various applications in protective or decorative films, coatings, separation membranes, sensing matrices, and optical and electrical devices. Sol-gel-derived thin films with specific functions have been gaining the most attention among the sol-gel materials (Brinker and Schever, 1990;Klein, 1988;Hench and West, 1990;Avnir, 1995;Lev et al, 1997;Dunwila et al, 1996;Dai et al, 1995;Dunbar et al, 1996;Sanchez and Ribot, 1994;Lu et al, 1997;Fehlner, 1997;Munro et al, 1997;Sakka, 1990). The ability to control the microstructural features of deposited films by ad-justing many variables, such as the nature of the precursor, composition, solvent, pH, temperature, and additives, is an advantage of sol-gel processing over conventional thin-film processing techniques (Brinker et al, 1992;Mehrotra, 1990;Sanchez and In, 1992;Corriu and Leclercq, 1996;Brinker and Schever, 1985).…”