Mössbauer spectra and electric properties of57Fe-enriched BiFeO3thin films

57 Fe-enriched BiFeO 3 (BFO) thin films are fabricated on Pt/Ti/SiO 2 /Si substrates from a stoichiometric precursor solution by chemical solution deposition process. The microstructure of the thin films is controlled by a changing the sintering time at 550 °C. The polycrystalline thin film fabricated at 550 °C for 5 min shows well-saturated polarization–electric field ( P – E ) hysteresis loops and the remnant polarization P r and coercive field E c at room temperature are 52 µC/cm 2 and 365 kV/cm, respectively, at an applied electric field of 1200 kV/cm. The Mössbauer spectra show that the BFO thin film has the valence state of Fe 3+ only, consisting of antiferromagnetic and paramagnetic components. The paramagnetic component with an area fraction from 11 to 18%, which is not amorphous or Bi 2 Fe 4 O 9 , seems to distribute in the surface shell of the grains and the grain boundaries. This component must strongly influence the ferroelectric properties at room temperature.