Preparation and Properties of Ferroelectric 0.7BiFeO3-0.3BaTiO3 Thin Films by Chemical Solution Deposition

抄録

Ferroelectric 0.7BiFeO3-0.3BaTiO3 and 0.7BiFe0.95Mn0.05O3-0.3BaTi03 thin films have been prepared by the chemical solution deposition. Perovskite single-phase thin films with homogeneous surface morphology were successfully fabricated at 700°C on Pt/TiOx/SiO2/Si substrates. Although typical polarization (F)-electric field (E) hysteresis loops were observed for 0.7BiFeO3-0.3BaTiO3 thin films, their insulation resistance was relatively low at room temperature. Mn doping for Fe site of the 0.7BiFeO3-0.3BaTiO3 was very effective in improving the leakage current property at high applied fields and the surface morphology of the resultant thin films. 5 mol% Mn-doped films exhibited larger ferroelectricity at room temperature. Furthermore, at a low temperature of -190°C, the remanent polarization (Pr) of the 700°C-prepared 0.7BiFeO3-0.3BaTiO3 and 0.7BiFe0.95Mn0.05O3-0.3BaTiO3 thin films were approximately 30 and 46 C/cm2, respectively.