Low resistance magnetic tunnel junctions and their interface structures

J. Fujikata, T. Ishi, S. Mori, K. Matsuda, K. Mori, H. Yokota, K. Hayashi, M. Nakada, A. Kamijo, Keishi Ohashi

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

Effects of interface structure and oxidation state were studied in stacked magnetic tunnel junction (MTJ) structures with top and bottom antiferromagnetic layers to obtain optimum resistance and high tunneling magnetoresistance (TMR) ratios for read heads. The roughness of the NiFe surface and the Al coverage were significantly improved by introduction of O2 surfactant gas on the Ta-seed-layer surface, which increased TMR ratios of the MTJ with low resistance area (RA) products of less than 10 Ω μm2. Furthermore, it was found that avoidance of Ni oxidation and Co oxidation at the tunnel barrier interface is essential to obtaining high TMR ratios, and that a good Al coverage and Fe-oxide formation may enhance TMR ratios when Fe-rich magnetic materials are used. For the top-type and bottom-type structures, a TMR ratio of 12%-17% with RA products of 6-7 Ω μm2 was obtained, which provides sufficient performance for read heads.

Original languageEnglish
Pages (from-to)7558-7560
Number of pages3
JournalJournal of Applied Physics
Volume89
Issue number11 II
DOIs
Publication statusPublished - 2001 Jun 1
Externally publishedYes

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low resistance
tunnel junctions
oxidation
avoidance
products
magnetic materials
tunnels
seeds
surface layers
roughness
surfactants
oxides
gases

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Physics and Astronomy (miscellaneous)

Cite this

Fujikata, J., Ishi, T., Mori, S., Matsuda, K., Mori, K., Yokota, H., ... Ohashi, K. (2001). Low resistance magnetic tunnel junctions and their interface structures. Journal of Applied Physics, 89(11 II), 7558-7560. https://doi.org/10.1063/1.1361054

Low resistance magnetic tunnel junctions and their interface structures. / Fujikata, J.; Ishi, T.; Mori, S.; Matsuda, K.; Mori, K.; Yokota, H.; Hayashi, K.; Nakada, M.; Kamijo, A.; Ohashi, Keishi.

In: Journal of Applied Physics, Vol. 89, No. 11 II, 01.06.2001, p. 7558-7560.

Research output: Contribution to journalArticle

Fujikata, J, Ishi, T, Mori, S, Matsuda, K, Mori, K, Yokota, H, Hayashi, K, Nakada, M, Kamijo, A & Ohashi, K 2001, 'Low resistance magnetic tunnel junctions and their interface structures', Journal of Applied Physics, vol. 89, no. 11 II, pp. 7558-7560. https://doi.org/10.1063/1.1361054
Fujikata J, Ishi T, Mori S, Matsuda K, Mori K, Yokota H et al. Low resistance magnetic tunnel junctions and their interface structures. Journal of Applied Physics. 2001 Jun 1;89(11 II):7558-7560. https://doi.org/10.1063/1.1361054
Fujikata, J. ; Ishi, T. ; Mori, S. ; Matsuda, K. ; Mori, K. ; Yokota, H. ; Hayashi, K. ; Nakada, M. ; Kamijo, A. ; Ohashi, Keishi. / Low resistance magnetic tunnel junctions and their interface structures. In: Journal of Applied Physics. 2001 ; Vol. 89, No. 11 II. pp. 7558-7560.
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