Multiferroic properties of (Bi, Ca)FeO3 films on glass substrates

Effect of Ca substitution on the multiferroic properties of non-epitaxially grown polycrystalline Bi1−xCaxFeO3 (BCFO) films on refined Pt(1 1 1) electrode buffered glass substrates is studied. The structural analysis shows that a pure perovskite phase with isotropic orientation is present for BCFO films (x = 0.05-0.15). The grain size and surface roughness are reduced with increasing x. Different from the BCFO ceramics, good ferroelectric properties with the remanent polarization (2Pr) of 91-124 μC/cm2 and electrical coercive field (Ec) of 294-394 kV/cm are obtained in BCFO polycrystalline thin films. Furthermore, the substitution of Ca2+ for Bi3+ effectively enhance the ferromagnetic properties with magnetization (Ms) of 5.9-8.2 emu/cm3 and coercivity (Hc) of 1224-1258 Oe. The ferromagnetic and ferroelectric properties and leakage behavior as functions of Ca content x are discussed.