Enhanced ferroelectricity and band gap engineering of (1- x )BiFeO 3 - x SrTiO 3 thin films

摘要: The (1-x)BiFeO3-xSrTiO3 (BFO-xSTO, x = 0, 0.05, 0.10, 0.20, 0.30) solid solution thin films were fabricated by a sol–gel method. X-ray diffraction patterns showed that phase transition appeared as the SrTiO3 modified BiFeO3. structural properties of all samples analyzed Raman spectroscopy. Scanning electron microscope images have dense and uniform surface morphology. Compared with BiFeO3 film, BFO-xSTO enhanced its ferroeletric significantly. BFO-0.20STO film possessed lowest leakage current larger polarization well-defined ferroelectric hysteresis loop. In order to investigate optical properties, ellipsometric spectra on Si substrates measured experimental data fitted using model consisting air/roughness/BFO-xSTO/Si(100). constants band gaps obtained. linear increase increasing content. results indicate promising ability for improving ferroelectricity introducing enable functionality multiferroic informational storage devices while tuning gap wide photovoltaic material.