Room temperature ferroelectric properties and leakage current characteristics of Bi2FeMnO6/SrTiO3 bilayered thin films by chemical solution deposition

Bi2FeMnO6/SrTiO3 (BFMO/STO) bilayered thin films were grown on LaNiO3 (LNO) buffered Si(100) substrate by chemical solution deposition. The structure and surface morphology of the bilayered thin films have been characterized by X-ray diffraction and atomic force microscopy. The Au/BFMO/STO/LNO thin-film capacitor showed well-saturated hysteresis loop at an applied field of 330 kV cm-1 with remnant polarization (2Pr) and coercive electric field (2Ec) values of 1.3 μC cm-2 and 80 kV cm-1, respectively. The films show leakage current density in the order of 10-5 A cm-2 in the whole electric field region. The leakage current depended on the voltage polarity. The Au/BFMO/STO interface forms an Ohmic contact with Au electrode biased negatively. At low electric field, the BFMO/STO/LNO interface forms an Ohmic contact with LNO electrode biased negatively. A further increase of applied electric field, the conduction shows a space-charge-limited-current behavior. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)