Advertisement

Photoconductivity and diode effect in Bi rich multiferroic BiFeO3 thin films grown by pulsed-laser deposition

  • K. Ahadi
  • S. M. Mahdavi
  • A. Nemati
  • M. Kianinia
Article

Abstract

Bismuth ferrite, BiFeO3, is almost the only material that is simultaneously magnetic and a strong ferroelectric at room temperature. As a result it is the most investigated multiferroic material. In this study, bismuth ferrite thin films were deposited on silicon wafer (100) and glass by pulsed-laser deposition and their structural, optical, and electrical properties were measured. Our study indicates that Bi richness in these films can stimulate formation of oxygen vacancy in the system which in its turn leads to delocalization of carriers and a more intensified photoconductivity response. X-ray diffraction analysis revealed formation of BiFeO3 (BFO), but it also showed formation of Bi2O3 and Bi2O2.3 as well as BFO. Energy dispersive spectrum (EDS) also showed higher atomic concentration of Bi with respect to Fe. It also disclosed Bi depletion through the films during post-growth heat treatment. Atomic force microscopy showed a homogeneous nano structure with columnar grains. It also disclosed that higher substrate temperature can improve smoothness of the films. Scanning electron microscopy depicted the thickness of about 200 nm. Transmission spectrum illustrated band gap of about 2 eV. Dark–light IV characteristics were conducted on the films which were subjected to post-growth heat treatment at 0.01 and 760 Torr O2. Dark conductivities increased by an order of magnitude in comparison between films which were subjected to post-growth heat treatment at 0.01 and 760 Torr O2. Dark–light IV characteristics of the films also uncovered a remarkable increase in conductivity under illumination in comparison to dark one. Diode behavior of the films was investigated by IV characteristics as well.

Keywords

Oxygen Vacancy Bi2O3 BiFeO3 Energy Dispersive Spectrum BiFeO3 Thin Film 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

The authors acknowledge the Research and Development Deputy of Sharif University of Technology for supporting this work. This work was also supported and funded by Iranian Nanotechnology Initiative Council. The authors also would like to acknowledge Mr. Mohammad Reza Nematollahi, Mr. Farhang Parsikia, Ms. Elham Nemati and Dr. Mehdi Ranjbar for their helps.

References

  1. 1.
    W. Eerenstein, N.D. Mathur, J.F. Scott, Nature 442, 759 (2006). doi: 10.1038/nature05023 (review)
  2. 2.
    R. Ramesh, N.A. Spaldin, Nat. Mater. 6, 21 (2007). doi: 10.1038/nmat1805 (review)
  3. 3.
    N.A. Spaldin, M. Fiebeg, Science 309, 391 (2005). doi: 10.1126/science.1113357 CrossRefGoogle Scholar
  4. 4.
    M. Fiebig, J. Phys. D 38, R123 (2005). doi: 10.1088/0022-3727/38/8/R01 CrossRefGoogle Scholar
  5. 5.
    N.A. Hill, J. Phys. Chem. B 104, 6694 (2000). doi: 10.1021/jp000114x CrossRefGoogle Scholar
  6. 6.
    S.W. Cheong, M. Mostovoy, Nat. Mater. 6, 13 (2007). doi: 10.1038/nmat1804 CrossRefGoogle Scholar
  7. 7.
    J. Wang, J.B. Neaton, H. Zheng, V. Nagarajan, S.B. Ogale, B. Liu, D. Viehland, V. Vaithyanathan, D.G. Schlom, U.V. Waghmare, N.A. Spaldin, K.M. Rabe, M. Wuttig, R. Ramesh, Science 299, 1719 (2003). doi: 10.1126/science.1080615 CrossRefGoogle Scholar
  8. 8.
    Y.H. Chu, L.W. Martin, M.B. Holcomb, M. Gajek, S.J. Han, Q. He, N. Balke, C.H. Yang, D. Lee, W. Hu, Q. Zhan, P.L. Yang, A.F. Rodríguez, A. Scholl, S.X. Wang, R. Ramesh, Nat. Mater. 7, 478 (2008). doi: 10.1038/nmat2184 CrossRefGoogle Scholar
  9. 9.
    S.R. Basu, L.W. Martin, Y.H. Chu, M. Gajek, R. Ramesh, R.C. Rai, X. Xu, J.L. Musfeldt, Appl. Phys. Lett. 92, 091905 (2008). doi: 10.1063/1.2887908. (3 p)CrossRefGoogle Scholar
  10. 10.
    T. Choi, S. Lee, Y.J. Choi, V. Kiryukhin, S.W. Cheong, Science 324, 63 (2009). doi: 10.1126/science.1168636 CrossRefGoogle Scholar
  11. 11.
    S.Y. Yang, L.W. Martin, S.J. Byrnes, T.E. Conry, S.R. Basu, D. Paran, L. Reichertz, J. Ihlefeld, C. Adamo, A. Melville, Y.H. Chu, C.H. Yang, J.L. Musfeldt, D.G. Schlom, J.W. Ager, R. Ramesh, Appl. Phys. Lett. 95, 062909 (2009). doi: 10.1063/1.3204695. (3 p)CrossRefGoogle Scholar
  12. 12.
    L. Bi, A.R. Taussig, H.S. Kim, L. Wang, G.F. Dionne, D. Bono, K. Persson, G. Ceder, C.A. Ross, Phys. Rev. B 78, 104 (2008). doi: 10.1103/PhysRevB.78.104106 CrossRefGoogle Scholar
  13. 13.
    Y. Wang, C.W. Nan, Thin Solid Films 517, 4484 (2009). doi: 10.1016/j.tsf.2009.02.142 CrossRefGoogle Scholar
  14. 14.
    H.M. Christen, G. Eres, J. Phys.: Condens. Matter 20, 264005 (2008). doi: 10.1088/0953-8984/20/26/264005 CrossRefGoogle Scholar
  15. 15.
    Y. Xu, M. Shen, Mater. Lett. 62, 3600 (2008). doi: 10.1016/j.matlet.2008.04.006 CrossRefGoogle Scholar
  16. 16.
    S.J. Clark, J. Robertson, Appl. Phys. Lett. 90, 132903 (2007). doi: 10.1063/1.2716868. (3 p)CrossRefGoogle Scholar
  17. 17.
    Y.P. Wang, L. Zhou, M.F. Zhang, X.Y. Chen, J.M. Liu, Z. Liu, Appl. Phys. Lett. 84, 1731 (2004). doi: 10.1063/1.1667612. (3 p)CrossRefGoogle Scholar
  18. 18.
    G.W. Pabst, L.W. Martin, Y.H. Chu, R. Ramesh, Appl. Phys. Lett. 90, 072902 (2007). doi: 10.1063/1.2535663. (3 p)CrossRefGoogle Scholar
  19. 19.
    K. Ahadi, A. Nemati, S.M. Mahdavi, M. Nematollahi, M. Ranjbar, Optical Properties of Bi Rich Multiferroic BiFeO3 Thin Films Grown by Pulsed Laser Deposition, in Proceedings of International Conference on Nanotechnology: Fundamentals and Applications, Ottawa, Ontario, Canada, 4–6 August 2010, paper no. 389Google Scholar
  20. 20.
    C.H. Yang, J. Seide, S.Y. Kim, P.B. Rossen, P. Yu, M. Gajek, Y.H. Chu, L.W. Martin, M.B. Holcomb, Q. He, P. Maksymovych, N. Balke, S.V. Kalinin, A.P. Baddorf, S.R. Basu, M.L. Scullin, R. Ramesh, Nat. Mater. 8, 485 (2009). doi: 10.1038/NMAT2432 CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • K. Ahadi
    • 1
  • S. M. Mahdavi
    • 2
    • 3
  • A. Nemati
    • 1
  • M. Kianinia
    • 1
  1. 1.Department of Materials Science and EngineeringSharif University of TechnologyTehranIran
  2. 2.Physics DepartmentSharif University of TechnologyTehranIran
  3. 3.Institute for Nanoscience and NanotechnologySharif University of TechnologyTehranIran

Personalised recommendations