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:
Oct. 17, 1995
Filed:
Aug. 16, 1994
Hitoshi Isono, Tenri, JP;
Hirotoshi Takemori, Nara, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
A method of manufacturing a stamper includes the steps of coating a flat surface of a substrate with photosensitive material; directing light to a specified position on the photosensitive material to expose it; developing the photosensitive material to make a minute photoresist pattern; etching the substrate to a specified depth with a mask of the photoresist pattern; removing the photoresist as the mask to make a glass master; arbitrarily forming a first nickel layer on a surface of the glass master; forming an intermediate layer of a metal having a smaller linear expansion coefficient than nickel over the first nickel layer; forming a second nickel layer on the intermediate layer to form a conductive film having a two- or three-stratum structure; arbitrarily subjecting the whole substrate to a process to make nickel passive; forming an electroformed layer on the conductive film by an electroforming process; and separating the conductive film from the glass master.