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:
Nov. 24, 2009
Filed:
Sep. 14, 2005
Koichi Nishioka, Kanagawa, JP;
Shuichi Kojima, Kanagawa, JP;
Koji Kataoka, Kanagawa, JP;
Takayoshi Ohtsu, Kanagawa, JP;
Koichi Nishioka, Kanagawa, JP;
Shuichi Kojima, Kanagawa, JP;
Koji Kataoka, Kanagawa, JP;
Takayoshi Ohtsu, Kanagawa, JP;
Hitachi Global Storage Technologies Netherlands B.V., Amsterdam, NL;
Abstract
Embodiments of the invention provide a reading head structure that ensures a stable magnetic moment of a pinned layer against a great external magnetic field, and minimizes the pinned-layer damage occurring during air-bearing surface machining. In one embodiment, a magnetoresistive head is based on a spin-valve effect and has free layers, a stacked-type pinned layer, and an electroconductive nonmagnetic spacer layer positioned between the free layers and the stacked-type pinned layer. The stacked-type pinned layer includes three ferromagnetic films, and antiferromagnetic coupling films interposed between the ferromagnetic films. Of these ferromagnetic films, the first two films have a high coercivity and a high resistivity. The third ferromagnetic film is made of a material that gives a great magnetoresistive effect. The sum of the magnetic moments generated from the stacked-type pinned layer is substantially zero.