A multiferroic polycrystalline BiFeO3 film has been fabricated by a chemical solution deposition followed by the post deposition annealing at 823 K in air. The nanostructure of the BiFeO3 film was characterized by transmission electron microscopy (TEM). The nano-beam electron diffraction and the fast Fourier transform pattern image from the high resolution TEM image were compared with the electron diffraction patterns of the multislice simulation, and it was revealed that the BiFeO3 has R3c rhombohedral structure. Formation of any additional phase or phases was not found in the sample. The BiFeO3 film shows the small saturation magnetization of 5.2 emu/cm3 without spontaneous magnetization at room temperature, which behavior is typical for the weak ferromagnetic materials. The ferroelectric hysteresis loop of the BiFeO3 film was measured at low temperature in order to reduce the leakage current. The remanent polarization and the electric coercive field at 90 K were 52 μC/cm2 and 0.51 MV/cm at an applied electric field of 1.4 MV/cm, respectively. The structure-magnetic properties relationship is also discussed.
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