MgO barrier-perpendicular magnetic tunnel junctions with CoFe/Pd multilayers and ferromagnetic insertion layers

被引：120

作者：

Mizunuma, K. ^{[1
]}

Ikeda, S. ^{[1
]}

Park, J. H. ^{[1
]}

Yamamoto, H. ^{[1
,2
]}

Gan, H. ^{[1
]}

Miura, K. ^{[1
,2
]}

Hasegawa, H. ^{[1
]}

Hayakawa, J. ^{[2
]}

Matsukura, F. ^{[1
]}

Ohno, H. ^{[1
]}

机构：

[1] Tohoku Univ, Lab Nanoelect & Spintron, Elect Commun Res Inst, Aoba Ku, Sendai, Miyagi 9808577, Japan

[2] Hitachi Ltd, Adv Res Lab, Kokubunji, Tokyo 1858601, Japan

来源：

APPLIED PHYSICS LETTERS | 2009年 / 95卷 / 23期

关键词：

MAGNETORESISTANCE; ELECTRODES; ANISOTROPY; FILMS;

D O I：

10.1063/1.3265740

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The authors studied an effect of ferromagnetic (Co20Fe60B20 or Fe) layer insertion on tunnel magnetoresistance (TMR) properties of MgO-barrier magnetic tunnel junctions (MTJs) with CoFe/Pd multilayer electrodes. TMR ratio in MTJs with CoFeB/MgO/Fe stack reached 67% at annealing temperature (T-a) of 200 degrees C and then decreased rapidly at T-a over 250 degrees C. The degradation of the TMR ratio may be related to crystallization of CoFe(B) into fcc(111) or bcc(011) texture resulting from diffusion of B into Pd layers. MTJs which were in situ annealed at 350 degrees C just after depositing bottom CoFe/Pd multilayer showed TMR ratio of 78% by postannealing at T-a= 200 degrees C. (C) 2009 American Institute of Physics. [doi: 10.1063/1.3265740]

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页数：3

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