Synthetic ferrimagnet free layer tunnel junction for magnetic random access memories
- 15 May 2002
- journal article
- conference paper
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 91 (10) , 7700-7702
- https://doi.org/10.1063/1.1447530
Abstract
In this work a synthetic ferrimagnet structure as a spin dependent tunnel junction free layer is proposed as a magnetic random access memories cell. The CoFe/Ru/CoFe and CoFe/NiFe/Ru/NiFe/CoFe systems show antiferromagnetically coupling range >1000 Oe and rotate rigidly anti-aligned with coercive fields below 30–40 Oe. Tunnel junctions were patterned to 4 μm×2 μm rectangles and ellipses using standard CoFe/Ni and synthetic ferrimagnet free layers. Identical signal levels are measured (17.8% and 16.3% as-deposited). Switching fields are dominated by material anisotropy for the synthetic ferrimagnet structure. Both free layer types show reversal by domain wall motion. Less switching dispersion is found for synthetic ferrimagnet free layer (≈10 Oe), with magnetization reversal occurring mostly in sharp single steps.This publication has 5 references indexed in Scilit:
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