Stock material or miscellaneous articles – Magnetic recording component or stock – Magnetic head
Reexamination Certificate
2008-03-27
2011-11-15
Rickman, Holly (Department: 1785)
Stock material or miscellaneous articles
Magnetic recording component or stock
Magnetic head
C428S811100, C428S811200, C428S811300, C428S811400, C428S811500, C365S158000, C365S171000, C365S173000
Reexamination Certificate
active
08057925
ABSTRACT:
A dual spin filter that minimizes spin-transfer magnetization switching current (Jc) while achieving a high dR/R in STT-RAM devices is disclosed. The bottom spin valve has a MgO tunnel barrier layer formed with a natural oxidation process to achieve low RA, a CoFe/Ru/CoFeB—CoFe pinned layer, and a CoFeB/FeSiO/CoFeB composite free layer with a middle nanocurrent channel (NCC) layer to minimize Jc0. The NCC layer may have be a composite wherein conductive M(Si) grains are magnetically coupled with adjacent ferromagnetic layers and are formed in an oxide, nitride, or oxynitride insulator matrix. The upper spin valve has a Cu spacer to lower the free layer damping constant. A high annealing temperature of 360° C. is used to increase the MR ratio above 100%. A Jc0of less than 1×106A/cm2is expected based on quasistatic measurements of a MTJ with a similar MgO tunnel barrier and composite free layer.
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Horng Cheng T.
Tong Ru-Ying
Ackerman Stephen B.
Chau Linda
MagIC Technologies, Inc.
Rickman Holly
Saile Ackerman LLC
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