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:
Jun. 12, 2001
Filed:
Nov. 20, 1998
NEC Corporation, Tokyo, JP;
Abstract
A magnetic disk drive for recording and reproducing data out of a magnetic disk with a magnetoresisive (MR) head contacting the disk is disclosed. When the MR device is spaced from the surface of the medium by a recess of less than 15 nm inclusive, the surface of the medium is provided with a sheet resistance of less than 5 &OHgr;/cm,inclusive. When the sheet resistance is greater than 5 &OHgr;/cm,, the recess is selected to be 16 nm or above. To enhance a frequency characteristic, the surface of the disk is provided with an undulation period of greater than 2 &mgr;m inclusive in the direction of movement of a head and a surface roughness of less than 1 nm inclusive. With this configuration, the disk drive obviates electrical faults ascribable to the sliding contact of the head and disk.