Skip to main content
SpringerLink
Log in

Magnetoresistive sensors with hybrid Co/insulator/ZnO:Co junctions

  • Published:
International Journal of Minerals, Metallurgy, and Materials Aims and scope Submit manuscript

Abstract

Magnetic tunnel junctions (MTJs), as the seminal spintronic devices, are expected for applications in magnetoresistive sensors due to their large magnetoresistance (MR) and high field sensitivity. Two hybrid Co/insulator/ZnO:Co junctions were fabricated with two different barriers to investigate the magneto-transport properties. Experimental results indicate that, both Co/MgO/ZnO:Co and Co/ZnO/ZnO:Co junctions show the positive and nearly linear MR, and their tunnel magnetoresistances (TMR) are 21.8% and 13.6%, respectively, when the current is applied perpendicular to the film plane under the magnetic field of 2 T at 4 K. The nonlinearity of MR is less than 1% within the magnetic field (H) of 1 kOe < H < 12 kOe at low temperature, making them attractive as magnetoresistive sensors. The higher MR of Co/MgO/ZnO:Co junctions is due to the superior spin filtering effect and larger effective barrier height of the MgO barrier. This linear MR characteristic of Co/insulator/ZnO:Co structures shows a promising future on the applications of diluted magnetic semiconductors in magnetoresistive sensors.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. F.B. Mancoff, J.H. Dunn, B.M. Clemens, and R.L. White, A giant magnetoresistance sensor for high magnetic field measurements, Appl. Phys. Lett., 77(2000), No. 12, p. 1879.

    Article  CAS  Google Scholar 

  2. M. Urbaniak, F. Stobiecki, B. Szymanski, A. Ehresmann, A. Maziewski, and M. Tekielak, Magnetic and magnetoresistive properties of NiFe/Au/Co/Au multilayers with perpendicular anisotropy of Co layers, J. Appl. Phys., 101(2007), No. 1, article No. 013905.

  3. S. van Dijken and J.M.D. Coey, Magnetoresistance sensor with an out-of-plane magnetized sensing layer, Appl. Phys. Lett., 87(2005), No. 2, article No. 022504.

    Google Scholar 

  4. M. Tondra, J.M. Daughton, D. Wang, R.S. Beech, A. Fink, and J.A. Taylor, Picotesla field sensor design using spindependent tunneling devices, J. Appl. Phys., 83(1998), No. 11, p. 6688.

    Article  CAS  Google Scholar 

  5. Y. Lu, R.A. Altman, A. Marley, S.A. Rishton, P.L. Trouilloud, G. Xiao, W.J. Gallagher, and S.S.P. Parkin, Shapeanisotropy-controlled magnetoresistive response in magnetic tunnel junctions, Appl. Phys. Lett., 70(1997), No. 19, p. 2610.

    Article  CAS  Google Scholar 

  6. B. Negulescu, D. Lacour, F. Montaigne, A. Gerken, J. Paul, V. Spetter, J. Marien, C. Duret, and M. Hehn, Wide range and tunable linear magnetic tunnel junction sensor using two exchange pinned electrodes, Appl. Phys. Lett., 95(2009), No. 11, article No. 112502.

  7. R.C. Chaves, P.P. Freitas, B. Ocker, and W. Maass, Low frequency picotesla field detection using hybrid MgO based tunnel sensors, Appl. Phys. Lett., 91(2007), No. 10, article No. 102504.

  8. H.X. Wei, Q.H. Qin, Z.C. Wen, X.F. Han, and X.G. Zhang, Magnetic tunnel junction sensor with Co/Pt perpendicular anisotropy ferromagnetic layer, Appl. Phys. Lett., 94(2009), No. 17, article No. 172902.

  9. H.X. Wei, Q.H. Qin, M. Ma, R. Sharif, and X.F. Han, 80% tunneling magnetoresistance at room temperature for thin Al-O barrier magnetic tunnel junction with CoFeB as free and reference layers, J. Appl. Phys., 101(2007), No. 9, article No. 09B501.

  10. S.S.P. Parkin, C. Kaiser, A. Panchula, P.M. Rice, B. Hughes, M. Samant, and S.H. Yang, Giant tunnelling magnetoresistance at room temperature with MgO (100) tunnel barriers, Nat. Mater., 3(2004), p. 862.

    Article  CAS  Google Scholar 

  11. S. Yuasa, T. Nagahama, A. Fukushima, Y. Suzuki, and K. Ando, Giant room-temperature magnetoresistance in single-crystal Fe/MgO/Fe magnetic tunnel junctions, Nat. Mater., 3(2004), p. 868.

    Article  CAS  Google Scholar 

  12. C. Song, F. Zeng, K.W. Geng, X.J. Liu, F. Pan, B. He, and W.S. Yan, Substrate-dependent magnetization in Codoped ZnO insulating films, Phys. Rev. B, 76(2007), No. 4, article No. 045215.

  13. Z.J. Gao, Y.S. Gu, X.Q. Wang, and Y. Zhang, Mechanical properties of Mn-doped ZnO nanowires studied by firstprinciples calculations, Int. J. Miner. Metall. Mater., 19(2012), No. 1, p. 89.

    Article  CAS  Google Scholar 

  14. Y.D. Gu, W.J. Mai, and P. Jiang, Characterization of structural and electrical properties of ZnO tetrapods, Int. J. Miner. Metall. Mater., 18(2011), No. 6, p. 686.

    Article  CAS  Google Scholar 

  15. S. Ramachandran, J.T. Prater, N. Sudhakar, D. Kumar, and J. Narayan, Magnetic properties of epitaxial oxide heterostructures, Solid State Commun., 145(2008), No. 1–2, p. 18.

    Article  CAS  Google Scholar 

  16. Q.Y. Xu, L. Hartmann, S.Q. Zhou, A. Mcklich, M. Helm, G. Biehne, H. Hochmuth, M. Lorenz, M. Grundmann, and H. Schmidt, Spin manipulation in Co-doped ZnO, Phys. Rev. Lett., 101(2008), No. 7, article No. 076601.

  17. G. Chen, F. Zeng, and F. Pan, Enhanced spin injection and voltage bias in (Zn,Co)O/MgO/(Zn,Co)O magnetic tunnel junctions, Appl. Phys. Lett., 95(2009), No. 23, article No. 232508.

  18. C. Song, X.J. Liu, F. Zeng, and F. Pan, Fully epitaxial (Zn,Co)O/ZnO/(Zn,Co)O junction and its tunnel magnetoresistance, Appl. Phys. Lett., 91(2007), article No. 042106.

    Google Scholar 

  19. H. Saito, A. Yamamoto, S. Yuasa, and K. Ando, High tunneling magnetoresistance in Fe/GaOx/Ga1−x MnxAs with metal/insulator/semiconductor structure, Appl. Phys. Lett., 93(2008), No. 17, article No. 172515.

  20. C. Song, F. Zeng, Y.X. Shen, K.W. Geng, Y.N. Xie, Z.Y. Wu, and F. Pan, Local Co structure and ferromagnetism in ion-implanted Co-doped LiNbO3, Phys. Rev. B, 73(2006), No. 17, article No. 172412.

  21. H. Toyosaki, T. Fukumura, K. Ueno, M. Nakano, and M. Kawasaki, A ferromagnetic oxide semiconductor as spin injection electrode in magnetic tunnel junction, Jpn. J. Appl. Phys., Part 2, 44(2005), p. L896.

    Article  CAS  Google Scholar 

  22. J.M. de Teresa, A. Barthélémy, A. Fert, J.P. Contour, F. Montaigne, and P. Seneor, Role of metal-oxide interface in determining the spin polarization of magnetic tunnel junctions, Science, 286(1999), No. 5439, p. 507.

    Article  Google Scholar 

  23. K. Ghosh, S.B. Ogale, S.P. Pai, M. Robson, E. Li, I. Jin, Z.W. Dong, R.L. Greene, R. Ramesh, T. Venkatesan, and M. Johnson, Positive giant magnetoresistance in a Fe3O4/SrTiO3/La0.7Sr0.3MnO3 heterostructure, Appl. Phys. Lett., 73(1998), No. 5, p. 689.

    Article  CAS  Google Scholar 

  24. P.Y. Yang, X.Y. Zhu, G. Chen, F. Zeng, and F. Pan, Hysteretic giant magnetoresistance curves induced by interlayer magnetostatic coupling in [Pd/Co]/Cu/Co/Cu/[Co/Pd]_dual spin valves, J. Appl. Phys., 107(2010), No. 8, article No. 083902.

  25. F. Montaigne, J. Nassar, A. Vaur`es, F.N. Van Dau, F. Petroff, A. Schuhl, and A. Fert, Enhanced tunnel magnetoresistance at high bias voltage in double-barrier planar junctions, Appl. Phys. Lett., 73(1998), No. 19, p. 2829.

    Article  CAS  Google Scholar 

  26. B. Carvello, C. Ducruet, B. Rodmacq, S. Auffret, E. Gautier, G. Gaudin, and B. Dieny, Sizable room-temperature magnetoresistance in cobalt based magnetic tunnel junctions with out-of-plane anisotropy, Appl. Phys. Lett., 92(2008), No. 10, article No. 102508.

Download references

Author information

Authors and Affiliations

  1. Laboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China

    Guang Chen, Cheng Song & Feng Pan

Authors
  1. Guang Chen
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Cheng Song
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Feng Pan
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Cheng Song.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Chen, G., Song, C. & Pan, F. Magnetoresistive sensors with hybrid Co/insulator/ZnO:Co junctions. Int J Miner Metall Mater 20, 160–165 (2013). https://doi.org/10.1007/s12613-013-0708-5

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s12613-013-0708-5

Keywords

Search

Navigation