Improved multiferroic properties in Sm-doped BiFeO3 thin films deposited using chemical solution deposition method

摘要

Sm-substituted (0% to 10%) BiFeO3 thin films were fabricated by chemical solution deposition on Pt/Ti/SiO2/Si substrates. X-ray diffraction analysis revealed that no secondary phase appeared even if Bi atoms were substituted with Sm atoms up to 10 at. %. 7.5 at. % Sm-substituted films show improved electrical properties and substitution was effective in improving the coercive field in the films. Sm-substitution shows improved ferroelectric as well as magnetic properties of the films. There is a noticeable reduction in the leakage current density (10-4 A/cm2) and increase in the polarization (70 μC/cm2) when the Sm concentration is kept around 7.5%. The magnetic moment obtained from the saturated magnetization curves shows a value of 0.3 μB/Fe compared to 0.04 μB/Fe for the parent compound. The results are important since it increases the potential of the material as a multiferroic compound.