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:
Sep. 17, 2002
Filed:
Oct. 16, 2000
David William Abraham, Ossining, NY (US);
Philip Edward Batson, Katonah, NY (US);
William Joseph Gallagher, Ardsley, NY (US);
Stuart Parkin, San Jose, CA (US);
John Slonczewski, Katonah, NY (US);
Philip Louis Trouilloud, Mahwah, NJ (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
Magnetoresistive devices are disclosed which include a changeable magnetic region within which at least two magnetic states can be imposed. Upon magnetoresistive electrical interaction with the device, the relative orientation of the magnetic states of the changeable magnetic region, and a proximate reference magnetic region, can be sensed thereby providing a binary data storage capability. The present invention limits the electrical interaction to only a preferred portion of the changeable magnetic region, e.g., the portion within which the two magnetic states can be dependably predicted to be substantially uniform, and opposite of one another. Structures for limiting the electrical interaction to this preferred portion of the changeable magnetic region are disclosed, and include smaller interaction regions, and alternating areas of insulation and conductive, interaction regions, disposed proximate the changeable magnetic region. The principles of the present invention can be applied to magnetic random access memory (“MRAM”) arrays, which employ giant magnetoresistive (“GMR”) cells, or magnetic tunnel junction (“MTJ”) cells, at the intersections of bitlines and wordlines, and also to magnetic sensors such as magnetic data storage devices having access elements used to access data on a magnetic data storage medium.