Electrical properties of (001)- and (116)-oriented epitaxial SrBi2Ta2O9 thin films prepared by metalorganic chemical vapor deposition

Abstract
(001)- and (116)-oriented epitaxial SrBi2Ta2O9 (SBT) thin films were deposited on (100)SrRuO3∥(100)SrTiO3 substrates at 750 °C and (110)SrRuO3∥(110)SrTiO3 substrates at 820 °C by metalorganic chemical vapor deposition, respectively. The remanent polarization and the coercive field of the 200-nm-thick (116)-oriented SBT films normal to the substrate were 11.4 μC/cm2 and 80 kV/cm, respectively. The dielectric constant of this film was 140 at 1 kHz. On the other hand, the 200-nm-thick (001)-oriented SrBi2Ta2O9 films normal to the substrate showed no ferroelectricity and the dielectric constant was 70 at 1 kHz.