Epitaxial SrBi2Ta2O9 (SBT) thin films with well-defined (001), (116), and (103) orientations have been grown by pulsed laser deposition on (001)-, (011)-, and (111)-oriented Nb-doped SrTiO3 substrates. X-ray diffraction pole figure and φ-scan measurements revealed that the three-dimensional epitaxial orientation relation SBT(001)‖SrTiO3(001), and SBT[11̄0]‖SrTiO3[100] is valid for all cases of SBT thin films on SrTiO3 substrates, irrespective of their orientations. Atomic force microscopy images of the c-axis-oriented SBT revealed polyhedron-shaped grains showing spiral growth around screw dislocations. The terrace steps of the c-axis-oriented SBT films were integral multiples of a quarter of the lattice parameter c of SBT (∼0.6 nm). The grains of (103)-oriented SBT films were arranged in a triple-domain configuration consistent with the symmetry of the SrTiO3(111) substrate. The measured remanent polarization (2Pr) and coercive field (2Ec) of (116)-oriented SBT films were 9.6 μC/cm2 and 168 kV/cm, respectively, for a maximum applied electric field of 320 kV/cm. Higher remanent polarization (2Pr=10.4 μC/cm2) and lower coercive field (2Ec=104 kV/cm) than those of SBT(116) films were observed in (103)-oriented SBT thin films, and (001)-oriented SBT revealed no ferroelectricity along the [001] axis. The dielectric constants of (001)-, (116)-, and (103)-oriented SBT were 133, 155, and 189, respectively.

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The initial growth mechanism of epitaxial BaTiO 3 films is studied by combined application of atomic force microscopy, cross sectional high-resolution transmission electron microscopy, and x-ray diffraction. Epitaxial BaTiO 3 thin films were grown by pulsed laser deposition on vicinal Nb-doped SrTiO 3 (SrTiO 3 :Nb) ͑001͒ substrates with well-defined terraces. X-ray diffraction and cross sectional high-resolution transmission electron microscopy investigations revealed well-defined epitaxial films and a sharp interface between BaTiO 3 films and SrTiO 3 :Nb substrates. The layer-then-island ͑Stranski-Krastanov mode͒ growth mechanism observed by analyzing the morphology of a sequence of films with increasing amount of deposited material has been confirmed by microstructure investigations.