Influence of cobalt ferrite on the magnetoelectric properties of thin films of bismuth ferrite deposited by spin coating

摘要

The films composed of (1-x) BiFeO3- (x) CoFe2O4 varying the concentration (x = 0, 0.1, 0.2 and 0.3) were deposited by spin coating on Pt substrate (Pt / TiO2/ SiO2/ Si) from of 0.05 molar concentration precursors solutions, which were obtained by sol-gel method. Thin films characterization was made, the structure and the magnetoelectric properties were studied using X-ray diffraction, leakage current, dielectric constant, ferroelectric and ferromagnetic hysteresis curve. The XRD results show characteristic peaks with the formation of BiFeO3 and the growth of peaks belonging to CoFe2O4 with the increase of x. All samples reveal little leakage current, being the lowest of 10(-10) A/cm(2) for (0.8) BiFeO3- (0.2) CoFe2O4. The dielectric constant increased in the range from 10(2) Hz to 10(5) Hz then decreased due to dielectric relaxation, for all samples the dielectric loss is less than 4%. All fabricated films show remnants polarization and magnetization greater than 60 mu C/cm(2) and 30 emu/gr respectively.