Preparation and characterization of <i>a</i>- and <i>b</i>-axis-oriented epitaxially grown Bi4Ti3O12-based thin films with long-range lattice matching

a- and b-axis-oriented epitaxial Bi4Ti3O12 films were prepared on (101)TiO2 (rutile) substrates at 630 °C by metalorganic chemical vapor deposition and their perfect epitaxial growths were confirmed by several x-ray diffraction measurements. As the bottom electrode, (101)-oriented conductive materials with the same rutile-type structure as the TiO2, RuO2, and IrO2, were epitaxially grown on (101)TiO2, (012)Al2O3, and (110)Al2O3 substrates. Finally, a- and b-axis-oriented Bi4Ti3O12-based materials, (Bi4−xNdx)(Ti3−yVy)O12, were epitaxially grown on these conductive substrates with high reproducibility and a well-saturated P–E hysteresis loop with a remanent polarization above 20 μC/cm2 was observed. These results open the long-range lattice matching growth (the c-axis lattice parameter is about 3.3 nm) of a- and b-axis-oriented bismuth layer-structured ferroelectrics on conductive electrodes.