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:
Jan. 06, 1998
Filed:
Jan. 07, 1997
Motokazu Yamamoto, Tokyo, JP;
Noriko Nakamura, Tokyo, JP;
Abstract
An object of the present invention is to provide a method for manufacturing a magnetic hard disk wherein a magnetic material layer adhered on a surface of a substrate of the magnetic hard disk has a flat surface. A method for manufacturing a magnetic hard disk comprising steps of: structurally transforming a surface of an amorphous Ni--P alloy film layer formed a substrate (10) of the magnetic hard disk; and adhering a magnetic material layer on the surface of a substrate (10), wherein the step of structurally transforming the a-Ni--P alloy film layer is a step of heating only a desired portion of the surface of the substrate (10) by an electric discharge to generate Ni and crystallized compounds of Ni and P only at the desired portion (T) of the surface thereof. The electric discharge in the step of structurally transforming the a-Ni--P alloy film layer is carried out by applying a discharge potential between at least one electric discharger (11) and a metallic table (12) as an electrode which carries the substrate (10) thereon, the electric discharger (11) being positioned in opposite to the surface of the substrate (10).