Multiferroic properties of Bi1−xAxFeO3 polycrystalline films on glass substrates (A = Ca, Sr, Ba and x=0.05–0.15)

• Perovskite single phase is confirmed in Bi1−xAxFeO3 polycrystalline films.
• BAFO films on refined Pt electrode show fine microstructure and flat surface.
• Different from bulks, BAFO films achieve coexistence of good FE and FM properties.
• BAFO films are a highly potential multiferroic material for advanced applications.

Bi1−xAxFeO3 (BAFO) polycrystalline films (A = Ca, Sr, and Ba; x = 0.05, 0.1, and 0.15) were deposited on an optimized 20-nm-thick Pt bottom electrode on glass substrates at 450 °C via pulsed laser deposition. Perovskite single phase is confirmed in all studied BAFO films. With increasing content of the substituents, the refinement of microstructure and surface roughness becomes more obvious. Different from BAFO bulks, the studied BAFO polycrystalline films achieve coexistence of good ferroelectric and ferromagnetic properties. Remanent polarization (2Pr) of 47–124 μC/cm2 and electrical coercive field of 290–557 kV/cm are obtained, while the saturation magnetization of 5.9–13.9 emu/cm3 and coercivity of 1211–1380 Oe are attained for the substitution of Ca2+, Sr2+, or Ba2+ for Bi3+. The multiferroic properties and leakage behavior with A substitution and as a function of its content x are also discussed.