Effect of high annealing temperature on giant tunnel magnetoresistance ratio of CoFeB/MgO/CoFeB magnetic tunnel junctions

被引：167
作者：
Hayakawaa, J.
Ikeda, S.
Lee, Y. M.
Matsukura, F.
Ohno, H.
机构：
[1] Hitachi Ltd, Adv Res Lab, Kokubunji, Tokyo 1858601, Japan
[2] Tohoku Univ, Elect Commun Res Inst, Lab Nanoelect & Spintron, Aoba Ku, Sendai, Miyagi 9808577, Japan
来源：
APPLIED PHYSICS LETTERS | 2006年 / 89卷 / 23期
关键词：
ROOM-TEMPERATURE; THERMAL-STABILITY; DEPENDENCE;
D O I：
10.1063/1.2402904
中图分类号：
O59 [应用物理学];
学科分类号：
摘要：
The authors report tunnel magnetoresistance (TMR) ratios as high as 472% at room temperature and 804% at 5 K in pseudo-spin-valve (PSV) CoFeB/MgO/CoFeB magnetic tunnel junctions (MTJs) annealed at 450 degrees C, which is approaching the theoretically predicted value. By contrast, the TMR ratios for exchange-biased (EB) SV MTJs with a MnIr antiferromagnetic layer are found to drop when they are annealed at 450 degrees C. Energy dispersive x-ray analysis shows that annealing at 450 degrees C induces interdiffusion of Mn and Ru atoms into the MgO barrier and ferromagnetic layers in EB-SV MTJs. Mechanisms behind the different annealing behaviors are discussed. (c) 2006 American Institute of Physics.
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