Static information storage and retrieval – Systems using particular element – Magnetoresistive
Reexamination Certificate
2007-09-14
2009-12-08
Lam, David (Department: 2827)
Static information storage and retrieval
Systems using particular element
Magnetoresistive
C365S171000, C365S173000
Reexamination Certificate
active
07630232
ABSTRACT:
A toggle MTJ cell is disclosed that has a nearly balanced SAF free layer with two major sub-layers separated by an anti-parallel coupling layer. Within each major sub-layer, there is a plurality of minor sub-layers wherein adjacent minor sub-layers are separated by a parallel coupling layer. The parallel coupling layer is a non-magnetic layer that may be a one or more of Ta, Cu, Cr, Ru, Os, Re, Rh, Nb, Mo, W, Ir, and V, a metal oxide, or dusting of NiCr, Ta, Cu, or NiFeCr. Magnetic moments of major sub-layers are made to be nearly equal so that the net moment of the SAF free layer is essentially zero. The MTJ cell and SAF free layer preferably have an aspect ratio of from 1 to 5. Ferromagnetic coupling between minor sub-layers enables a lower write current and lower power consumption than conventional toggle cell designs.
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Ackerman Stephen B.
Lam David
MagIC Technologies, Inc.
Saile Ackerman LLC
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