Enhanced tunneling magnetoresistance and perpendicular magnetic anisotropy in Mo/CoFeB/MgO magnetic tunnel junctions

被引:87
作者
Almasi, H. [1 ]
Hickey, D. Reifsnyder [2 ]
Newhouse-Illige, T. [1 ]
Xu, M. [1 ]
Rosales, M. R. [1 ]
Nahar, S. [3 ]
Held, J. T. [2 ]
Mkhoyan, K. A. [2 ]
Wang, W. G. [1 ]
机构
[1] Univ Arizona, Dept Phys, Tucson, AZ 85721 USA
[2] Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA
[3] Sunnyside High Sch, Dept Sci, Tucson, AZ 85706 USA
基金
美国国家科学基金会;
关键词
ROOM-TEMPERATURE; FILMS;
D O I
10.1063/1.4919873
中图分类号
O59 [应用物理学];
学科分类号
摘要
Structural, magnetic, and transport studies have been performed on perpendicular magnetic tunnel junctions (pMTJ) with Mo as the buffer and capping layers. After annealing samples at 300 degrees C and higher, consistently better performance was obtained compared to that of conventional pMTJs with Ta layers. Large tunneling magnetoresistance (TMR) and perpendicular magnetic anisotropy (PMA) values were retained in a wide range of samples with Mo layers after annealing for 2 h at 400 degrees C, in sharp contrast to the junctions with Ta layers, in which superparamagnetic behavior with nearly vanishing magnetoresistance was observed. As a result of the greatly improved thermal stability, TMR as high as 162% was obtained in junctions containing Mo layers. These results highlight the importance of the heavy-metal layers adjacent to CoFeB electrodes for achieving larger TMR, stronger PMA, and higher thermal stability in pMTJs. (C) 2015 AIP Publishing LLC.
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页数:5
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