Orientation dependent leakage current behaviors and ferroelectric polarizations of off-axis sputtered BiFeO3 thin films

Abstract Epitaxial BiFeO 3 thin films with (100), (110) and (111) orientations were grown on the SrRuO 3 -buffered SrTiO 3 substrates by using an off-axis magnetron sputtering. Unlike the BiFeO 3 (110) and BiFeO 3 (111) thin films that exhibited a single rhombohedral phase structure, a dominant rhombohedral phase accompanying with a small amount of tetragonal phase was identified in the BiFeO 3 (100) thin film. In particular, the leakage currents and ferroelectric polarizations of sputtered BiFeO 3 thin films were focused on and these films showed utterly different current density-electric field ( J - E ) behaviors whether in the positive or negative electric field. Among the three films, the ferroelectric polarization of the BiFeO 3 (100) thin film presented a good frequency stability and had the maximum remnant polarization of P r  ∼ 78 μC/cm 2 @ 10 kHz, which could be further demonstrated by pulsed polarizations of films. The distinct differences in electrical properties of orientation-engineered BiFeO 3 thin films in present case can be attributed to their different crystallographic orientations and microstructures.