Crystal structure and electrical properties of epitaxial SrBi2Ta2O9 films

The crystal structure and electrical properties were investigated for (001) - and (116)-oriented SrBi2Ta2O9 (SBT) thin films deposited on (100) SrTiO3 and (100)SrRuO(3)parallel to(100)SrTiO3 substrates, and (110) SrTiO3 and (1 10)SrRuO(3)parallel to(110)SrTiO3 substrates, respectively. Both oriented S BT films were epitaxially grown with high crystal perfection, and twinning existed in the (116)-oriented one. Both oriented SBT films were found to fo rm c/6 lattice displacements to relax the stress. The interface of the (001 )-oriented film did not include misfit dislocations, defects, and an interf acial layer, and that of the (116)-oriented film included the lattice strai n contrast due to an irregular atomic arrangement. The electrical property of the SBT film shows anisotropy of the ferroelectricity along the c- and a -axis directions; the remanent polarizations of the (001)- and (116)-orient ed SBT films were 0 and 10.5 mu C/cm(2), respectively. (C) 2000 American In stitute of Physics. [S0021-8979(00)02111-3].