Reduced leakage current in chemical solution deposited multiferroic BiFeO3/Ba0.25Sr0.75TiO3 heterostructured thin films on platinized silicon substrates

Multilayered metal-insulator-metal structures with BiFeO3 and Ba0.25Sr0.75TiO3 thin films were fabricated by chemical solution deposition to reduce the leakage current through the capacitor stack. The Ba0.25Sr0.75TiO3 layer does not influence the crystalline structure of BiFeO3 and was recognized as rhombohedral by Raman studies. Compared to pure BiFeO3, in the heterostructures, the coercivity increased, but the saturation magnetization and the leakage current were reduced. The frequency and the temperature dependence of the dielectric properties of the heterostructured film showed evidence of space charge developed between the layers of different dielectric constant (Ba0.25Sr0.75TiO3-BiFeO3 interface).