Impact of Tungsten Sputtering Condition on Magnetic and Transport Properties of Double-MgO Magnetic Tunneling Junction With CoFeB/W/CoFeB Free Layer

被引：20

作者：

Honjo, H. ^{[1
,7
]}

Ikeda, S. ^{[1
,2
,3
,7
]}

Sato, H. ^{[1
,2
,3
,4
]}

Nishioka, K. ^{[1
,7
]}

Watanabe, T. ^{[1
,7
]}

Miura, S. ^{[1
,7
]}

Nasuno, T. ^{[1
,7
]}

Noguchi, Y. ^{[1
,7
]}

Yasuhira, M. ^{[1
,7
]}

Tanigawa, T. ^{[1
,7
]}

Koike, H. ^{[1
,7
]}

Inoue, H. ^{[1
,7
]}

Muraguchi, M. ^{[1
,5
,7
]}

Niwa, M. ^{[1
,7
]}

Ohno, H. ^{[1
,2
,3
,4
,6
,7
]}

Endoh, T. ^{[1
,2
,3
,5
,7
]}

机构：

[1] Tohoku Univ, Ctr Innovat Integrated Elect Syst, Sendai, Miyagi 9800845, Japan

[2] Tohoku Univ, Ctr Spintron Integrated Syst, Sendai, Miyagi 9808577, Japan

[3] Tohoku Univ, Ctr Spintron Res Network, Sendai, Miyagi 9808577, Japan

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

[5] Tohoku Univ, Grad Sch Engn, Sendai, Miyagi 9808579, Japan

[6] Tohoku Univ, WPI Adv Inst Mat Res, Sendai, Miyagi 9808577, Japan

[7] Japan Sci & Technol Agcy JST, ACCEL, Kawaguchi, Saitama 3320012, Japan

来源：

IEEE TRANSACTIONS ON MAGNETICS | 2017年 / 53卷 / 11期

基金：

日本科学技术振兴机构;

关键词：

CoFeB-MgO; double interfaces structure; interfacial anisotropy; magnetic tunnel junction (MTJ); perpendicular anisotropy; spin-transfer-torque magnetoresistive random access memory (STT-MRAM);

D O I：

10.1109/TMAG.2017.2701838

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

We investigated an effect of sputtering gas species (Ar, Kr, and Xe) for deposition of a W insertion layer in the CoFeBW/ CoFeB free layer on magnetic properties of the free layer and tunnel magnetoresistance (TMR) ratio of magnetic tunnel junctions (MTJs) stacks using the free layer annealed at 400 degrees C for 1 h. As the W insertion layer thickness tW increased, we found the degradation of perpendicular anisotropy and larger reduction of saturation magnetic moment per unit area mS in the free layer using Ar compared to those using Kr and Xe. We also found a smaller TMR ratio for the MTJ stack using Ar compared to those using Kr and Xe. Energy-dispersive X-ray spectrometry line analysis revealed more significant interdiffusion between W and CoFeB layers in the free layer using Ar than those using Kr and Xe, that could result in the smaller mS and perpendicular anisotropy in the free layer and smaller TMR ratio for the MTJ stack using Ar than those using Kr and Xe. We also investigated concentration of Ar, Kr, and Xe in W layers deposited using Ar, Kr, and Xe, respectively, by high-resolution Rutherford backscattering spectrometry, revealing that 0.2 at% Ar was detected in theW layer using Ar, while Kr and Xe were not detected inW layers using Kr and Xe. Such a difference in concentration of inert gas atoms in the W layer could be one possible reason for the difference about degree of interdiffusion between W and CoFeB layers.

引用

页数：4

共 17 条

[1]

[Anonymous], S VLSI TECHN

[2]

[Anonymous], P IEEE INT MEM WORKS

[3]

[Anonymous], 2013, P IEEE S VLSI CIRC V

[4]

[Anonymous], 2014, S VLSI TECHN VLSI TE

[5]

[Anonymous], VLSI TECHNOLOGY

[6]

Chung SW, 2016, INT EL DEVICES MEET

[7] Three-terminal magnetic tunneling junction device with perpendicular anisotropy CoFeB sensing layer [J].

Honjo, H. ;

Fukami, S. ;

Ishihara, K. ;

Nebashi, R. ;

Kinoshita, K. ;

Tokutome, K. ;

Murahata, M. ;

Miura, S. ;

Sakimura, N. ;

Sugibayashi, T. ;

Kasai, N. ;

Ohno, H. .

JOURNAL OF APPLIED PHYSICS, 2014, 115 (17)

[8]

Ikeda S, 2010, NAT MATER, V9, P721, DOI [10.1038/NMAT2804, 10.1038/nmat2804]

[9] Magnetic properties of Fe films deposited by Ar, Kr, and Xe ion beam sputtering [J].

Iwatsubo, S ;

Takahashi, T ;

Naoe, M .

JOURNAL OF APPLIED PHYSICS, 1998, 83 (11) :6667-6669

[10]

Kang S.H., 2014, Symp. VLSI Technol, P1, DOI [10.1109/VLSIT.2014.6894354, DOI 10.1109/VLSIT.2014.6894354]

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