Structural and ferroic properties of Zr-doped BiFeO3 thin films

Polycrystalline Zr-doped BiFeO3 thin films were prepared by a sol-gel spin-coating technique on (111) Pt/Ti/SiO2/Si substrates. The films are of single phase as evidenced by X-ray diffraction, and microstructure characterization on the surface and cross-section morphology of the films was carried out by scanning electron microscope. By introducing a small amount of Zr ions into the sol-gel solution-processed BiFeO3 films, the leakage current density is reduced by three orders of magnitude compared with the undoped BiFeO3 films, and the conduction mechanism in the BiFeO3 -based films was studied. Both the films exhibit weak ferromagnetism of 25 emu/cm(3) at room temperature.