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:
Mar. 15, 2005
Filed:
Sep. 22, 2003
Tetsunori Koda, Moriya, JP;
Hideaki Yamanaka, Toride, JP;
Enji Fujita, Matsudo, JP;
Satoshi Matsunuma, Kamakura, JP;
Tetsunori Koda, Moriya, JP;
Hideaki Yamanaka, Toride, JP;
Enji Fujita, Matsudo, JP;
Satoshi Matsunuma, Kamakura, JP;
Hitachi Maxell, Ltd., Osaka, JP;
Abstract
A magnetic recording medium based on the perpendicular recording system, which has high coercivity and low medium noise, is provided by using an underlayer which has a thin film thickness and which makes it possible to improve the orientation of a recording layer. The magnetic recording medium based on the perpendicular recording system has the recording layer which is formed of a CoPtCr alloy magnetic film containing oxygen. The magnetic recording medium has such a structure that an adhesive layer, a soft magnetic back layer, the underlayer, the recording layer, and a protective layerare successively stacked on a substrate. A CoCrRu film, which has a film thickness of 5 nm to 20 nm, is used as the underlayer for the recording layer formed of the CoPtCr alloy magnetic film containing oxygen. Thus, it is possible to improve the crystalline orientation of the recording layer with the underlayer having the thin film thickness.