• DocumentCode
    1321688
  • Title

    Annealing Temperature and Co Layer Thickness Dependence of Magnetoresistance Effect for L1_{0} -MnGa/Co/MgO/CoFeB Perpendicular Magnetic Tunnel Junctions

  • Author

    Ma, Q.L. ; Kubota, T. ; Mizukami, S. ; Zhang, X.M. ; Oogane, M. ; Naganuma, H. ; Ando, Y. ; Miyazaki, T.

  • Author_Institution
    WPI Adv. Inst. for Mater. Res., Tohoku Univ., Sendai, Japan
  • Volume
    48
  • Issue
    11
  • fYear
    2012
  • Firstpage
    2808
  • Lastpage
    2811
  • Abstract
    The post annealing temperature and Co thickness dependence of tunnel magnetoresistance (TMR) ratio was investigated for L10-MnGa/Co(tCo)/MgO/CoFeB perpendicular magnetic tunnel junctions (MTJs). The MnGa/MgO interface optimization by Co insertion was shown to be an effective way for improving the TMR ratio. The TMR value increases with the annealing temperature (Ta), and exhibits maxima at 325 °C for tCo = 1.0 - 5.0 nm. Thermal annealing process improves the structure of MTJs, but also causes elements diffusion. In this work, the annealing effect on MTJs with different Co thicknesses was discussed in detail along with a fast annealing method.
  • Keywords
    annealing; boron alloys; cobalt; cobalt alloys; gallium alloys; iron alloys; magnesium compounds; magnetic multilayers; manganese alloys; tunnelling magnetoresistance; Co insertion; Co layer thickness dependence; MnGa-Co-MgO-CoFeB; MnGa-Co-MgO-CoFeB perpendicular magnetic tunnel junctions; MnGa-MgO interface optimization; annealing effect; element diffusion; fast annealing method; magnetic tunnel junction structure; magnetoresistance effect; post annealing temperature dependence; size 1 nm to 5 nm; temperature 325 degC; thermal annealing process; tunnel magnetoresistance ratio; Annealing; Junctions; Magnetic tunneling; Magnetization; Magnetoresistance; Manganese; $L1_{0}$ MnGa; perpendicular magnetic tunnel junctions (MTJs);
  • fLanguage
    English
  • Journal_Title
    Magnetics, IEEE Transactions on
  • Publisher
    ieee
  • ISSN
    0018-9464
  • Type

    jour

  • DOI
    10.1109/TMAG.2012.2196420
  • Filename
    6332842