Characterization of highly (117)-oriented Bi3.25La0.75Ti3O12 thin films prepared by rf-magnetron sputtering technique

Ferroelectric Bi3.25La0.75Ti3O12 (BLT) thin films were deposited on Pt(111)/Ti/SiO2/Si substrates at 400 °C using rf-magnetron sputtering method. The microstructures were studied by X-ray diffraction, scanning electron microscopy and energy dispersive spectrometer. The as-deposited thin film is amorphous, while transformed to microcrystalline and well crystalline states after annealing at 650 °C and 750 °C, respectively. After annealing at 750 °C, the polycrystalline BLT thin film showed plated-like grains all with (117)-preferred orientation. Analyses of ferroelectric properties indicated that, comparing with the as-deposited thin film, the highly (117)-oriented crystalline thin film exhibited well-saturated hysteresis loops with a superior remnant polarization (2Pr) of 30.7 μC/cm2.