Impedance spectroscopy studies on polycrystalline BiFeO3 thin films on Pt/Si substrates

Amar Srivastava, Ashish Garg, Finlay D. Morrison

Research output: Contribution to journalArticlepeer-review

Abstract

In this paper, we report on the results of temperature dependent impedance measurements on chemical solution deposited BiFeO3 thin films on Pt/Si substrates. X-ray diffraction analysis showed the presence of predominately single phase BiFeO3. The measurements were made in the frequency range of 100-10(7) Hz and between 27 and 250 degrees C. Plots between real and imaginary parts of impedance (Z(') and Z(')) and electrical modulus (M-' and M-') in the above frequency and temperature domain suggest the presence of two relaxation regimes which are attributed to bulk and grain boundary responses. Below 150 degrees C, both conductivity and real dielectric constant show a steplike behavior. The frequency independent regions in 10-100 kHz indicate relaxation of the bulk conduction, while at lower frequency there is a strong frequency dependence associated with the dispersion toward relaxation of the grain boundary. In contrast, at and above 150 degrees C, frequency independent behavior of dc conduction becomes dominant. The bulk dielectric constant was estimated as similar to 225, which is close to the values reported in the literature. Estimated grain and grain boundary conductivity activation energies are 0.28 and 0.81 eV, respectively.

Original languageEnglish
Article number054103
Pages (from-to)-
Number of pages6
JournalJournal of Applied Physics
Volume105
Issue number5
DOIs
Publication statusPublished - 1 Mar 2009

Keywords

  • bismuth compounds
  • dielectric relaxation
  • dielectric thin films
  • electrical conductivity
  • electrochemical impedance spectroscopy
  • grain boundaries
  • liquid phase deposition
  • multiferroics
  • permittivity
  • X-ray diffraction

Fingerprint

Dive into the research topics of 'Impedance spectroscopy studies on polycrystalline BiFeO3 thin films on Pt/Si substrates'. Together they form a unique fingerprint.

Cite this