Ferroelectric thin films of bismuth-containing layered perovskites: Part I, Bi4Ti3O12

Ferroelectric thin films of bismuth-containing layered perovskite Bi4Ti3O12 have been fabricated by a metalorganic decomposition (MOD) method. Crack-f ree and crystalline films of similar to 5000 Angstrom thickness have been d eposited on Pt/Ti/SiO2/Si substrates, Different heat treatments have been s tudied to investigate the nucleation and growth of perovskite Bi4Ti3O12 cry stallites. If the same composition and final annealing temperature are used , films with different orientations are obtained by different heating sched ules. These films show a large anisotropy in ferroelectric properties. Theo retical considerations are presented to suggest that nucleation control is responsible for texture and grain-size evolution. Moreover, the origin of t he ferroelectric anisotropy is rooted in the two-dimensional nature of laye red polarization.