DocumentCode :
1321688
Title :
Annealing Temperature and Co Layer Thickness Dependence of Magnetoresistance Effect for 
-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
Link To Document :
