Influence of different electrode on the property of epitaxial BiFeO3 thin film

Epitaxial BiFeO3(BFO) thin film have been grown on SrRuO3/SrTiO3(001) substrates by radio frequency magnetron sputtering. Ferroelectric, ferromagnetic, leakage current and its mechanisms were investigates with different metal and conductive oxide top electrode. X-ray diffraction measurement and Φ scan spectra indicates the formation of an epitaxial single-phase. BFO film is well crystallized. The remnant polarization(2Pr) of BFO film by Pt and Al top electrode are 68 μC/cm2. They are 44 μC/cm2 by Pt/SRO and FePt top electrode at a coercive field(2Ec) of 370±20 kV/cm. The film has low leakage current density with largest of 1.94×10-3 A/cm2 at 12 V and Poole-Frenkle emission is the main conduction mechanism in BFO film. Moreover, BFO thin film exhibits a weak ferromagnetic behavior with a saturation magnetization of 9.3 emu/cm3 and a coercive field of 338 Oe.