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. 21, 1994
Filed:
Mar. 19, 1993
Applicant:
Inventors:
Motoharu Sato, Kobe, JP;
Stephen S Rosenblum, Palo Alto, CA (US);
Assignees:
Kabushiki Kaisha Kobe Seiko Sho, Kobe, JP;
Kobe Steel USA Inc., New York, NY (US);
Primary Examiner:
Int. Cl.
CPC ...
B44C / ;
U.S. Cl.
CPC ...
156643 ; 156626 ; 156654 ;
Abstract
Disclosed is a method of manufacturing a carbon substrate for a magnetic disk capable of increasing the treatment rate leading to a lowering of the manufacturing cost, reducing the variation of the surface roughness of each substrate, and the variation of the surface roughness among the substrates in each lot. The surface of a carbon substrate is roughened to have a surface roughness Ra of 10-500 .ANG. by dry etching. The examples of the dry etching methods include chemical dry etching, barrel etching, plasma etching, RIE, RIBE, and ion milling.