Strain behavior of lanthanum modified BiFeO3 thin films prepared via soft chemical method

摘要

Pure and lanthanum modified BFO (LaxBi1-xFeO3, x=0.0, 0.08, 0.15, 0.30) thin films were fabricated on Pt(111)/Ti/SiO2/Si substrates by the soft chemical method. The effect of La substitution on the structural and electrical properties was studied. Scanning electron microscopy, x-ray diffraction, and Raman spectroscopy have been employed to characterize the thin films while the piezoelectric measurements were carried out using a setup based on an atomic force microscope. It was found that La-doped BFO thin films exhibited good ferroelectric properties, such as improved leakage current density and retention-free characteristics. The unipolar strain is strongly reduced by the amount of lanthanum added to the system.