Ferroelectric thin films of bismuth-containing layered perovskites: Part III, SrBi2Nb2O9 and c-oriented Bi4Ti3O12 template

Randomly and c-oriented SrBi2Nb2O9 thin films have been obtained by a metal organic decomposition (MOD) method using a highly c-oriented Bi4Ti3O12 laye r as a template. This templating procedure is generally applicable to other layered perovskites, and it has the advantage of lowering the temperature for crystallization and texture selection for these thin films. Moreover, t he c-oriented Bi4Ti3O12 template can serve as a bottom electrode at the sam e time. Ferroelectric and dielectric properties measured for SrBi2Nb2O9 fil ms of different orientations reveal strong anisotropy following the general trend known for other layered perovskites. Systematic differences in polar ization and coercive field can be consistently explained in terms of the di fferent m values and the lack of lone-pair electrons, The latter contribute to a higher polarization and a higher coercive field for SrBi2Nb2O9 thin f ilms.