Mn4+:BiFeO3/Zn2+:BiFeO3 bilayered thin films of (1 1 1) orientation

Abstract

Ferroelectric and fatigue behavior of bilayered thin films consisting of Mn4+-modified BiFeO3 and Zn2+-modified BiFeO3, which were deposited on SrRuO3-buffered Pt coated silicon substrates, were systematically investigated. The (1 1 1) orientation is induced for the BiFe0.95Mn0.05O3/BiFe 0.95Zn0.05O3 bilayer, due to the introduction of the bottom BiFe0.95Zn0.05O3 layer. With increasing the thickness ratio of the BiFe0.95Mn0.05O 3 layer, their leakage current decreases, and the fatigue endurance is greatly improved owing to the introduction of the BiFe0.95Mn 0.05O3 layer with a lower fatigue rate. The BiFe 0.95Mn0.05O3/BiFe0.95Zn 0.05O3 bilayer with the thickness ratio of 3:1 exhibits a larger remanent polarization of 2Pr ∼ 161.0 μC/cm2 than those of bilayers with different thickness ratios, while their coercive field slightly increases with increasing the thickness ratio of the BiFe 0.95Mn0.05O3 layer. © 2011 Elsevier B.V.