Abstract: Apparatus for detecting defects in a magnetic disk includes a read head including multiple read elements for reading multiple tracks of the disk. Read signals produced by the read elements are received by certifier circuit portions for determining whether any of the read signals includes an indication of a defect in the disk. A monitoring circuit monitors the read elements to detect a malfunctioning read element. The read head position is controlled so that a malfunctioning read element is not used.
Abstract: Nowadays, in fabricating a magnetic recording medium, a disk substrate is first mechanically polished to form an even surface. Next, a laser texturing process is performed to produce a textured annular landing zone on the disk substrate. A magnetic layer is then formed on the disk substrate to complete the fabrication process. However, abnormal asperity usually remains on the surface of the disk substrate. Further, as the amount of exposure time in the air increases, an oxide film is inevitably formed on the surface of the disk substrate. Both of them degrade the surface smooth of the disk substrate, resulting in poor control of the size and structure of the laser texture. In addition, due to the irregular distribution of the mechanical polished texture on the disk substrate, a subsequently formed magnetic layer can not easily achieve the desired properties. This invention therefore provides a light texture process for fabricating a magnetic recording medium.
Type:
Grant
Filed:
January 6, 1998
Date of Patent:
August 15, 2000
Assignee:
Trace Storage Technology Corporation
Inventors:
Cheng-Der Lin, Jason S. Lin, Yuan-Ming Chang, An-Hung Tan