Ferroelectric Properties Improvement of Mn-Doped 0.7BiFeO3-0.3BaTiO3 Thin Films Fabricated by Chemical Solution Deposition
Ferroelectric 0.7BiFeO3-0.3BaTiO3 and 0.7BiFe0.95Mn0.05O3-0.3BaTiO3 thin films were 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 (P)-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 leakage current properties. In 0.7BiFe0.95Mn0.05O3-0.3BaTiO3 thin films, the abrupt increase in leakage current was suppressed even at high electric fields, leading to the well-shaped P-E hysteresis loops at ambient temperatures. Remanent polarization and coercive field of the 0.7Bi (Fe0.95Mn0.05)O3-0.3Bi0.5Na0.5TiO3 films at room temperature were approximately 26 μC/cm2 and 130 kV/cm, respectively.