ORIENTATION DEPENDENCE OF FERROELECTRIC AND DIELECTRIC PROPERTIES IN CaBi4Ti4O15 THIN FILMS.

Ferroelectric CaBi4Ti4O15 (CBTi) thin films with random orientation and high c-axis orientation were prepared on a Pt(111)/Ti/SiO2/Si(100) substrate by a chemical solution deposition method. We observed a strong dependence of ferroelectric and dielectric properties on the film orientation. The CBTi thin film with random orientation exhibited remnant polarization (2Pr) of 54 μ C/cm2 at an applied electric field of 250 kV/cm and dielectric constant (ε) of 412 at a frequency of 1 kHz. The values of 2Pr and ε were larger than those observed in the CBTi thin film with high c-axis orientation. In addition, the randomly oriented thin film showed lower leakage current density than the highly c-axis-oriented thin film. [ABSTRACT FROM AUTHOR]