Structural and electrical properties of epitaxial SBT thin films by PLD

Ferroelectric SrBi2Ta2O9 (SBT) thin films have been grown epitaxially on YB CO/LaAlO3 (100) substrates by using a Nd:YAG pulsed laser deposition techni que. The films are found to be highly c-axis oriented epitaxial and the x-r ay diffraction (XRD) rocking curves show a narrow FWHM about 0.84 degrees f or SET (0012) peak. The high epitaxial quality of such films are also evide nced by XRD phi scans, and atomic force microscopy (AFM) measurements, whic h reveal a mosaic structure of the SET films. The feature size of the mosai cs is around 1 mu m with an average roughness of about 10nm. The electrical properties of the films such as polarization, dielectric permittivity have also been studied. It is found that the polarization of SET along c-axis i s much very small (Pr=1.1 mu C/cm(2)) and the dielectric constant of the ep itaxial film is around 200.