In-situ growth of high-quality epitaxial BiFeO3 thin film via off-axis RF magnetron sputtering

This work demonstrates an in-situ heteroepitaxial growth of BiFeO3 thin film on the SrRuO3-buffered (100) SrTiO3 substrate via off-axis radio-frequency (RF) magnetron sputtering. The coexistence of a dominant rhombohedral-like phase and a small amount of tetragonal-like phase of BiFeO3 thin film with a good (100) orientation was revealed. Furthermore, the fabricated BiFeO3 thin film exhibited the enhanced electrical properties, e.g. a reduced leakage current (J < 3.2 × 10−3 A/cm2) and a low loss (tanδ < 0.087), as well as a large intrinsic polarization of 2Pr ∼ 124 μC/cm2 with a coercive field of 2Ec ∼ 408 kV/cm. This finding can provide a simple and feasible in-situ sputtering technique for the high-quality thin films.