BI4TI3O12 THIN-FILMS FROM MIXED BISMUTH-TITANIUM ALKOXIDES

Bi4Ti3O12 thin films were obtained by the sol-gel method. The precurso r solution was prepared by allowing the two metallic alkoxides, Bi(OC2 H4OCH3)(3) and Ti(OC2H4OCH3)(4), to react in 2-methoxy-ethanol to form the mixed alkoxide. This stable sol was deposited by spin-coating ont o platinized silicon substrates. X-Ray diffraction patterns indicate t hat the perovskite initial crystallization temperature is 460 degrees C for powder samples and it ranges between 400 and 500 degrees C, for thin films, as a function of the number of coating layers. Dense, smoo th and crack free thin films with grain sizes ranging from 20 nm to 50 0 nn are obtained, depending on the number of coating layers and on th e post-deposition temperature annealing.