Bilayered BiFe0.95Mn0.05O3/Bi 0.90La0.10FeO3 thin films with low ferroelectric coercivity and large remanent polarization

Abstract

Bilayered thin films consisting of (Bi0.90La0.10) FeO3 and Bi(Fe0.95Mn0.05)O3, i.e., Bi(Fe0.95Mn0.05)O3/(Bi0.90La 0.10)FeO3, were deposited on SrRuO3 buffered SrTiO3(111) substrates by off-axis radio frequency magnetic sputtering, where (111)-oriented bilayered thin films were obtained. The bilayered Bi(Fe0.95Mn0.05)O3/(Bi 0.90La0.10)FeO3 thin film possesses a lower coercive field (2Ec∼335.6 kV/cm) and a larger remanent polarization (2Pr∼155.2 μC/cm2) at room temperature, and a higher relative permittivity as compared with those of single-layer (Bi0.90La0.10)FeO3 and Bi(Fe 0.95Mn0.05)O3 thin films, together with an improvement of the magnetic properties (2Ms∼31.2 emu/cm 3). The bottom (Bi0.90La0.10)FeO3 nanolayer promotes the growth of the Bi(Fe0.95Mn0.05) O3 layer, which are largely responsible for the multiferroic behavior observed. © 2010 The American Ceramic Society.