Synthesis and Characterization of BiFeO₃–PbTiO₃ Thin Films through Metalorganic Precursor Solution

Perovskite (1- x )BiFeO 3 – x PbTiO 3 thin films have been synthesized by the chemical solution deposition of metalorganic compounds. Homogeneous and stable BiFeO 3 –PbTiO 3 precursor solutions were prepared by selecting appropriate starting materials and 2-methoxyethanol as a solvent. Perovskite BiFeO 3 –PbTiO 3 powder samples with a composition ranging from x =0.1 to 0.5 showed weak ferromagnetism at room temperature. Perovskite BiFeO 3 –PbTiO 3 single-phase thin films on Pt/TiO x /SiO 2 /Si substrates with good surface morphology were also fabricated by optimizing the PbTiO 3 content. Ferroelectric polarization–electric field ( P – E ) hysteresis loops were observed for 0.7BiFeO 3 –0.3PbTiO 3 thin films, although some leakage current components are included at room temperature. The electrical resistivity of the BiFeO 3 –PbTiO 3 films was improved in the low temperature region, and the remnant polarization and coercive field of the 700 °C-prepared 0.7BiFeO 3 –0.3PbTiO 3 thin films at -190 °C were approximately 50 µC/cm 2 and 150 kV/cm, respectively. Furthermore, Mn doping into BiFeO 3 –PbTiO 3 was effective in improving the ferroelectric properties of the resultant thin films at room temperature.