Thickness-dependent ferroelectric properties of Mn-doped BiFeO3 films formed on Pt and SrRuO3/Pt electrodes by RF Sputtering

Mn-doped BiFeO3 (BFMO) films with various thicknesses were deposited on Pt(111) and SrRuO3(SRO)/Pt(111) bottom electrodes using radio-frequency (RF) sputtering at 550 °C. As the thickness of BFMO films was decreased, the coercive voltages (Vc) decreased while the coercive fields increased in the films on both Pt and SRO/Pt bottom electrodes. At a BFMO film thickness of 70 nm formed on the SRO/Pt(111) electrode, Vc was reduced to 3.4 V, while the remanent polarization was kept at a value as large as 56 μC/cm2.