Visible Raman and Impedance Spectroscopy Analysis of Bismuth-Rich Bismuth Ferrite Ceramic

The differing magneto-electric properties at either side of certain temperature of multiferroic materials like bismuth ferrite abbreviated as BFO, is an emerging research field for its applications, especially for possible use as magneto-electric random access ferroic memory devices. Generally high density electronic devices are fabricated in the form of thin films and preparation of thin films require Bi-rich BFO as target material due to volatility of bismuth. Thorough characterization of any material is a prerequisite before it is ready for device applications. In this paper the various Raman modes and impedance spectroscopic study of bismuth-rich BFO prepared by solid state method are reported. The different charge states of iron play an important role in the charge transportation behavior of this sample. So X-ray photo electron spectroscopic, abbreviated as XPS, analysis for charge ratio variation of iron with temperature change is also reported here. This paper also discusses the change of ratio of different charge densities in the sample for transportation in elevated temperatures, which is an important factor for use it in high temperature device applications.