Excellent Room-Temperature Ferroelectricity in Mn-Substituted BiFeO3 Thin Films Formed by Chemical Solution Deposition

摘要

Mn-substituted BiFeO3 (BFO) thin films were formed by chemical solutions deposition on Pt/Ti/SiO2/Si(100) structures. Effects of the Mn-substitution on the lattice structure and ferroelectricity of BFO films were examined. It was found that the lattice structure of the films was sensitive to the Mn-substitution and the secondary phase appeared in a 50% Mn-substituted BFO film. The leakage current densities were increased with the Mn-substitution. However, BFO films with Mn concentration of 3 to 7% showed lower leakage current than undoped BFO films in a higher electric field than 0.5 MV/cm. In these films, the saturated P-E hysteresis loops with remanent polarization of approximately 100 uC/cm2were obtained at RT, due to the low leakage current.