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:
Oct. 21, 1997
Filed:
Jun. 07, 1995
Kenneth Ting-Yuan Kung, San Jose, CA (US);
Po-Kang Wang, San Jose, CA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A magnetoresistive (MR) sensor comprising a layer of ferromagnetic material forming an MR sensing element wherein the MR sensor is biased by utilizing only the MR stripe uniaxial anisotropy and the shape anisotropy of the active region of the sensing element. The active region of the MR element has a generally square geometry to provide the desired shape anisotropy. The MR sensor is biased at approximately 45 degrees by defining the magnetization at the four edges of the sense element active region utilizing its shape anisotropy and canting the magnetic easy axis at an appropriate angle during fabrication of the MR sensor. To minimize Barkhausen noise, a single magnetic domain configuration is achieved by reducing the sensor active region dimensions, i.e., stripe height and track width, to less than the characteristic domain wall thickness such that the formation of multiple magnetic domains is no longer energetically favorable. A magnetic biasing material such as a layer of antiferromagnetic material to provide exchange coupling, can be provided at a pair of opposing edges to maintain the magnetization at the edges in the desired orientation and to stabilize the sensor.