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:
Apr. 03, 2012
Filed:
Apr. 17, 2009
Masahiko Hatatani, Kanagawa, JP;
Katsuro Watanabe, Ibaraki-Ken, JP;
Nubuo Yoshida, Kanagawa, JP;
Katsumi Hoshino, Kanagawa, JP;
Masahiko Hatatani, Kanagawa, JP;
Katsuro Watanabe, Ibaraki-Ken, JP;
Nubuo Yoshida, Kanagawa, JP;
Katsumi Hoshino, Kanagawa, JP;
Hitachi Global Storage Technologies Netherlands BV, Amsterdam, NL;
Abstract
Embodiments of the present invention provide a magnetic head having a read head of stable reading operation and with less magnetic fluctuation noise. According to one embodiment, a free layer has a structure comprising two ferromagnetic layers (a first free layer and a second free layer) that are coupled anti-ferromagnetically by way of a non-magnetic intermediate layer, in which the magnetization amount of the first free layer is set to larger than the magnetization amount of the second free layer. Further, the magnetic domains in the first free layer and the second free layer are stabilized simultaneously by increasing the distance between the second free layer and the magnetic domain control film to be more than the distance between the first free layer and the magnetic domain control film, thereby adjusting the magnetization amount of the magnetic domain control film. Further, the volume of the entire free layer is increased thereby greatly decreasing the magnetic fluctuation noises, to obtain a read head showing a high SN ratio.