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:
May. 04, 1999
Filed:
Oct. 02, 1995
Fujitsu Limited, Kawasaki, JP;
Abstract
A non-magnetic substrate, a Cu layer having a film thickness ranging from 0.5 to 10 nm, a Cr layer having a film thickness of 100 nm or less, a magnetic layer made of CoCrPt alloy in which a percentage content of Cr ranges from 12 atoms % to 20 atoms % and a percentage content of Pt ranges from 4 atoms % to 18 atoms %, a protective layer and a lubricating layer are arranged in that order to form a magnetic recording medium. Because the Cu layer is sufficiently thinned, a medium noise is sufficiently reduced, and a medium S/N ratio is sufficiently heightened. Because the film thickness of the Cr layer is 100 nm or less, the medium noise is reduced. Because the composition of CoCrPt alloy is limited in the magnetic layer, the medium S/N ratio is heightened. In addition, it is preferred that another Cu layer having a film thickness ranging from 0.5 to 10 nm be inserted into the magnetic layer to divide the magnetic layer into two layers. In this case, the medium noise is reduced by 20%, and the medium S/N ratio is heightened. Therefore, even though a magnetoresistive effect type magnetic head is used to record or reproduce information in/from the magnetic recording medium, the medium noise is sufficiently reduced, and the medium R/N ratio is sufficiently heightened.