Preparation and characterization of ferroelectric Bi₄Ti₃O₁₂ thin films grown on (100)-oriented silicon wafers

Ferroelectric bismuth titanate (Bi₄Ti₃O₁₂) thin films were prepared directly on (100) silicon substrate by rf planar magnetron sputtering using a Bi₂TiO₅ ceramic target. Highly c-axis-oriented films were obtained at a high deposition rate of about 17 nm/min. The deposited thin films, consisting of plate-like grains about 2 μm in diameter, were grown uniformly parallel to the substrate surface. The remanent polarization (P_r) and the coercive field (E_c) of this film at 50 Hz were estimated to be 0.8 μC/cm² and 20kV/cm, respectively.