Interlayer diffusion and specularity aspects of amorphous CoNbZr-based spin-valves

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

Interlayer diffusion, thermal stability, and specular scattering behaviors of spin-valves (SV) where CoNbZr films were employed in as under and capping layers have been investigated. CoNbZr 2 (or Ta 5)/CoFe/Cu/CoFe/IrMn/CoNbZr 0∼10 (or Ta 5) nm stacks were sputter-deposited on Si/SiO2 substrates. Both normalized MR ratio and exchange bias field (Hex) of a conventional Ta-based SV decreased monotonically about 50% upon exposure to postdeposition annealing at 300 °C. On the contrary, these values increased about 50% for CoNbZr-based SVs, in particular, as CoNbZr capping thickness was less than 4 nm. Surface depth profiling results suggest that Mn diffused into the pinned CoFe layer (inward) but not into the Ta capping layer (outward) for the Ta-based SV. Unlike in the Ta capping case, a CoNbZr capping layer promoted outward Mn diffusion resulting in a formation of thin Mn-oxide layer at the surface. We attribute the increase of MR ratio in CoNbZr-capped SVs to enhanced specularity due to the presence of thin Mn-oxide. However, the specular scattering effect is reduced by increasing the thickness of CoNbZr capping layer.

Original languageEnglish
Pages (from-to)2685-2687
Number of pages3
JournalIEEE Transactions on Magnetics
Volume38
Issue number5 I
DOIs
Publication statusPublished - 2002 Sep 1

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Oxides
interlayers
Scattering
Depth profiling
Thermodynamic stability
Annealing
Substrates
oxides
scattering
thermal stability
annealing

Keywords

  • Amorphous CoNbZr
  • Specularity
  • Spin valves
  • Thermal stability

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Physics and Astronomy (miscellaneous)

Cite this

Interlayer diffusion and specularity aspects of amorphous CoNbZr-based spin-valves. / Cho, Ho Gun; Kim, Young-geun; Lee, Seong Rae.

In: IEEE Transactions on Magnetics, Vol. 38, No. 5 I, 01.09.2002, p. 2685-2687.

Research output: Contribution to journalArticle

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