Co置換Biフェライト薄膜の室温での強誘電性および磁気特性

概要

論文の詳細を見る
Co substituted BiFeO3 polycrystalline films were fabricated on Pt/Ti/SiO2/Si(100) substrates by a chemical solution deposition method that was followed by post-deposition annealing between 673 and 1073 K. The substitution of cobalt at B-sites for iron in BiFeO3 was promoted at relatively high temperatures, and saturated at around 923 K. The leakage current density was suppressed by substituting Co; therefore, ferroelectricity could be observed at room temperature. The remanent polarization increased by substituting Co due to the reduced electric coercive field. The saturation magnetization increased by promoting Co substitution, and a magnetic coercive field of 1.5 kOe and remanent magnetization of 3 emu/cm3 were obtained by annealing at 923 K. This indicated that Co substituted BiFeO3 films are candidate materials that enable ferromagnetism and ferroelectricity to coexist above room temperature.
2009-05-01