Tunnel magnetoresistance of 604% at 300 K by suppression of Ta diffusion in CoFeB/MgO/CoFeB pseudo-spin-valves annealed at high temperature

被引：1217

作者：

Ikeda, S. ^{[1
]}

Hayakawa, J. ^{[2
]}

Ashizawa, Y. ^{[3
]}

Lee, Y. M. ^{[1
]}

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

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

Tsunoda, M. ^{[3
]}

Matsukura, F. ^{[1
]}

Ohno, H. ^{[1
]}

机构：

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

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

[3] Tohoku Univ, Dept Elect Engn, Sendai, Miyagi 9808579, Japan

来源：

APPLIED PHYSICS LETTERS | 2008年 / 93卷 / 08期

关键词：

D O I：

10.1063/1.2976435

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

The authors observed tunnel magnetoresistance (TMR) ratio of 604% at 300 K in Ta/Co20Fe60B20/MgO/Co20Fe60B20/Ta pseudo-spin-valve magnetic tunnel junction annealed at 525 degrees C. To obtain high TMR ratio, it was found critical to anneal the structure at high temperature above 500 degrees C, while suppressing the Ta diffusion into CoFeB electrodes and in particular to the CoFeB/MgO interface. X-ray diffraction measurement of MgO on SiO2 or Co20Fe60B20 shows that an improvement of MgO barrier quality, in terms of the degree of the (001) orientation and stress relaxation, takes place at annealing temperatures above 450 degrees C. The highest TMR ratio observed at 5 K was 1144%. (C) 2008 American Institute of Physics.

引用

页数：3

共 25 条

[1]

[Anonymous], 2007, IEEE INT SOLID STATE

[2]

Ashizawa Y., 2007, Journal of the Magnetics Society of Japan, V31, P411, DOI 10.3379/jmsjmag.31.411

[3] Spin-dependent tunneling conductance of Fe|MgO|Fe sandwiches -: art. no. 054416 [J].

Butler, WH ;

Zhang, XG ;

Schulthess, TC ;

MacLaren, JM .

PHYSICAL REVIEW B, 2001, 63 (05)

[4] Characterization of CoFeB electrodes for tunnel junctions [J].

Cardoso, S ;

Cavaco, C ;

Ferreira, R ;

Pereira, L ;

Rickart, M ;

Freitas, PP ;

Franco, N ;

Gouveia, J ;

Barradas, NP .

JOURNAL OF APPLIED PHYSICS, 2005, 97 (10)

[5] ALUMINUM FILMS DEPOSITED BY RF SPUTTERING [J].

DHEURLE, FM .

METALLURGICAL TRANSACTIONS, 1970, 1 (03) :725-&

[6] Spin transfer switching and spin polarization in magnetic tunnel junctions with MgO and AlOx barriers -: art. no. 232502 [J].

Diao, Z ;

Apalkov, D ;

Pakala, M ;

Ding, YF ;

Panchula, A ;

Huai, YM .

APPLIED PHYSICS LETTERS, 2005, 87 (23) :1-3

[7] 230% room-temperature magnetoresistance in CoFeB/MgO/CoFeB magnetic tunnel junctions [J].

Djayaprawira, DD ;

Tsunekawa, K ;

Nagai, M ;

Maehara, H ;

Yamagata, S ;

Watanabe, N ;

Yuasa, S ;

Suzuki, Y ;

Ando, K .

APPLIED PHYSICS LETTERS, 2005, 86 (09) :1-3

[8] Dependence of giant tunnel magnetoresistance of sputtered CoFeB/MgO/CoFeB magnetic tunnel junctions on MgO barrier thickness and annealing temperature [J].

Hayakawa, J ;

Ikeda, S ;

Matsukura, F ;

Takahashi, H ;

Ohno, H .

JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS, 2005, 44 (16-19) :L587-L589

[9] Effect of high annealing temperature on giant tunnel magnetoresistance ratio of CoFeB/MgO/CoFeB magnetic tunnel junctions [J].

Hayakawaa, J. ;

Ikeda, S. ;

Lee, Y. M. ;

Matsukura, F. ;

Ohno, H. .

APPLIED PHYSICS LETTERS, 2006, 89 (23)

[10]

HOSOMI M, INT EL DEV M, P459

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