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:
Jun. 05, 2007
Filed:
Jul. 15, 2005
Srinivas V. Pietambaram, Chandler, AZ (US);
Renu W. Dave, Chandler, AZ (US);
Jon M. Slaughter, Tempe, AZ (US);
Jijun Sun, Chandler, AZ (US);
Srinivas V. Pietambaram, Chandler, AZ (US);
Renu W. Dave, Chandler, AZ (US);
Jon M. Slaughter, Tempe, AZ (US);
Jijun Sun, Chandler, AZ (US);
Freescale Semiconductor, Inc., Austin, TX (US);
Abstract
A magnetic tunnel junction (MTJ), which is useful in magnetoresistive random access memories (MRAMs), has a free layer which is a synthetic antiferromagnet (SAF) structure. This SAF is composed of two ferromagnetic layers that are separated by a coupling layer. The coupling layer has a base material that is non-magnetic and also other materials that improve thermal endurance, control of the coupling strength of the SAF, and magnetoresistance ratio (MR). The preferred base material is ruthenium and the preferred other material is tantalum. Furthering these benefits, cobalt-iron is added at the interface between the tantalum and one of the ferromagnetic layers. Also the coupling layer can have even more layers and the materials used can vary. Also the coupling layer itself can be an alloy.