Characterization of columnar BiFeO₃ thick films prepared by magnetic field-assisted pulsed laser deposition

Polycrystalline BiFeO 3 thick films were prepared on Pt/TiO 2 /SiO 2 /Si substates by using magnetic field-assisted pulsed laser deposition. Columnar BiFeO 3 thick films were successfully obtained with a thickness of 1.8 μ m, owing to an oblique incoming flux and high deposition rate by the confinement of the plume under a magnetic field. In the columnar BiFeO 3 thick films, a saturated P-E hysteresis loop was obtained at RT, and the remanent polarization ( P r ) and coercive field ( E c ) were 42 μ C cm −2 and 380 kV cm −1 , respectively. Also, the piezoelectric response measured by atomic force microscopy showed a butterfly-shaped curve, and the piezoelectric d 33 coefficient was about 50 pm V −1 .