The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 11, 2009
Filed:
Nov. 15, 2006
Jijun Sun, Chandler, AZ (US);
Renu W. Dave, Chandler, AZ (US);
Jason A. Janesky, Gilbert, AZ (US);
Jon M. Slaughter, Tempe, AZ (US);
Jijun Sun, Chandler, AZ (US);
Renu W. Dave, Chandler, AZ (US);
Jason A. Janesky, Gilbert, AZ (US);
Jon M. Slaughter, Tempe, AZ (US);
Everspin Technologies, Inc., Chandler, AZ (US);
Abstract
Methods and apparatus are provided for magnetic tunnel junctions (MTJs) () employing synthetic antiferromagnet (SAF) free layers (). The MTJ () comprises a pinned ferromagnetic (FM) layer (), the SAF () and a tunneling barrier () therebetween. The SAF () has a first higher spin polarization FM layer () proximate the tunneling barrier () and a second FM layer () desirably separated from the first FM layer () by a coupling layer (), with magnetostriction adapted to compensate the magnetostriction of the first FM layer (). Such compensation reduces the net magnetostriction of the SAF () to near zero even with high spin polarization proximate the tunneling barrier (). Higher magnetoresistance ratios (MRs) are obtained without adverse affect on other MTJ () properties. NiFe combinations are desirable for the first () and second () free FM layers, with more Fe in the first () free layer and less Fe in the second () free layer. CoFeB and NiFeCo are also useful in the free layers.