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. 15, 2008
Filed:
Dec. 16, 2003
Junichi Sato, Nara, JP;
Hiroshi Fuji, Soraku-gun, JP;
Kunio Kojima, Nabari, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
To suppress a magnetic wall movement in the structure including an amorphous magnetic layer as a recording layer, and to realize a high density recording with a sufficient signal quality level, a magnetic recording medium includes an amorphous magnetic layer (recording layer) formed on a substrate, a non-magnetic metal element layer (underlayer) formed between the substrate and the amorphous magnetic layer, wherein an average surface roughness Ra of the non-magnetic metal element layer is in a range of 0.7 nm to 2.0 nm. The foregoing structure having the non-magnetic metal element layer of a large average surface roughness Ra brings about a great pinning effect onto the amorphous magnetic layer, thereby forming magnetic bits under stable conditions when carrying out a high density recording.