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. 31, 2004
Filed:
Apr. 09, 2001
Masayoshi Hiramoto, Nara, JP;
Nozomu Matsukawa, Nara, JP;
Akihiro Odagawa, Nara, JP;
Kenji Iijima, Kyoto, JP;
Hiroshi Sakakima, Kyoto, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
The present invention provides a magnetic head having improved characteristics, using a magnetoresistive device in which current flows across the film plane such as a TMR device. In a first magnetic head of the present invention, when the area of a non-magnetic layer is defined as a device cross-section area, and the area of a yoke is defined as a yoke area, viewed along the direction perpendicular to the surface of the substrate over which the yoke and the magnetoresistive device are formed, then the device cross-section area is not less than 30% of the yoke area, so that a resistance increase of the device cross-section area is suppressed. In a second magnetic head of the present invention, a magnetoresistive device is formed on a substrate, and a yoke is provided above a non-magnetic layer constituting the device. In a third magnetic head of the present invention, the free layer of the magnetoresistive device includes at least two magnetic films and at least one non-magnetic film that are laminated alternately, and the thickness of the non-magnetic layer is not less than 2 nm and not more than 10 nm, and magnetostatic coupling is dominant. In a fourth magnetic head of the present invention, a magnetic gap is provided adjacent to the magnetoresistive device and the magnetic films are coupled antiferromagnetically.