Semiconductor device manufacturing: process – Having magnetic or ferroelectric component
Reexamination Certificate
2006-11-15
2009-08-11
Menz, Douglas M (Department: 2891)
Semiconductor device manufacturing: process
Having magnetic or ferroelectric component
C257S295000, C257SE29167, C365S173000
Reexamination Certificate
active
07572645
ABSTRACT:
Methods and apparatus are provided for magnetic tunnel junctions (MTJs) (10, 50) employing synthetic antiferromagnet (SAF) free layers (14, 14′). The MTJ (10, 50) comprises a pinned ferromagnetic (FM) layer (32, 18), the SAF (14) and a tunneling barrier (16) therebetween. The SAF (14) has a first higher spin polarization FM layer (30) proximate the tunneling barrier (16) and a second FM layer (26) desirably separated from the first FM layer (30) by a coupling layer (28), with magnetostriction adapted to compensate the magnetostriction of the first FM layer (30). Such compensation reduces the net magnetostriction of the SAF (14) to near zero even with high spin polarization proximate the tunneling barrier (16). Higher magnetoresistance ratios (MRs) are obtained without adverse affect on other MTJ (10, 50) properties. NiFe combinations are desirable for the first (30) and second (26) free FM layers, with more Fe in the first (30) free layer and less Fe in the second (26) free layer. CoFeB and NiFeCo are also useful in the free layers.
REFERENCES:
patent: 5966323 (1999-10-01), Chen et al.
patent: 6114719 (2000-09-01), Dill et al.
patent: 6127045 (2000-10-01), Gill
patent: 6600184 (2003-07-01), Gill
patent: 6665155 (2003-12-01), Gill
patent: 6674617 (2004-01-01), Gill
patent: 6946697 (2005-09-01), Pietambaram
patent: 2006/0093862 (2006-05-01), Parkin
patent: 2006/0152681 (2006-07-01), Yamakawa et al.
International Search Report and Written Opinion.
Dave Renu W.
Janesky Jason A.
Slaughter Jon M.
Sun Jijun
Everspin Technologies, Inc.
Fulk Steven J
Ingrassia Fisher & Lorenz P.C.
Menz Douglas M
LandOfFree
Magnetic tunnel junction structure and method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Magnetic tunnel junction structure and method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic tunnel junction structure and method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4122706