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. 16, 2005
Filed:
Dec. 23, 2003
Matthew Joseph Carey, San Jose, CA (US);
Hoa Van DO, Fremont, CA (US);
Robin Frederick Charles Farrow, San Jose, CA (US);
Bruce Alvin Gurney, San Rafael, CA (US);
David Thomas Margulies, Gilroy, CA (US);
Ronald Franklin Marks, San Jose, CA (US);
Philip Milton Rice, San Jose, CA (US);
Ren Xu, San Jose, CA (US);
Matthew Joseph Carey, San Jose, CA (US);
Hoa Van Do, Fremont, CA (US);
Robin Frederick Charles Farrow, San Jose, CA (US);
Bruce Alvin Gurney, San Rafael, CA (US);
David Thomas Margulies, Gilroy, CA (US);
Ronald Franklin Marks, San Jose, CA (US);
Philip Milton Rice, San Jose, CA (US);
Ren Xu, San Jose, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
An exchange-coupled magnetic structure of a cobalt-ferrite layer adjacent a magnetic metal layer is used in magnetorestive sensors, such as spin valves or tunnel junction valves. The exchange-coupled magnetic structure is used in a pinning structure pinning the magnetization of a ferromagnetic pinned layer, or in an AP pinned layer. A low coercivity ferrite may be used in an AP free layer. Cobalt-ferrite layers may be formed by co-sputtering of Co and Fe in an oxygen/argon gas mixture, or by sputtering of a CoFecomposition target in an oxygen/argon gas mixture. Alternatively, the cobalt-ferrite layer may be formed by evaporation of Co and Fe from an alloy source or separate sources along with a flux of oxygen atoms from a RF oxygen atom beam source. Magnetoresistive sensors including cobalt-ferrite layers have small read gaps and produce large signals with high efficiency.