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 language | English |
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Pages (from-to) | 2685-2687 |
Number of pages | 3 |
Journal | IEEE Transactions on Magnetics |
Volume | 38 |
Issue number | 5 I |
DOIs | |
Publication status | Published - 2002 Sept |
Event | 2002 International Magnetics Conference (Intermag 2002) - Amsterdam, Netherlands Duration: 2002 Apr 28 → 2002 May 2 |
Bibliographical note
Funding Information:Manuscript received February 14, 2002; revised April 14, 2002. This work was supported by the Korea Ministry of Science and Technology under the National Research Laboratory Program, Contract NANO-MAT2G-10, the National Program for Tera-level Nanodevices, and the Basic Research Program of the Korea Science and Engineering Foundation under Grant 2000-2-30100-009-3.
Keywords
- Amorphous CoNbZr
- Specularity
- Spin valves
- Thermal stability
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering