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:
May. 14, 1991
Filed:
May. 02, 1989
Hirotoshi Tabuchi, Yamanashi, JP;
Osamu Kumasaka, Yamanashi, JP;
Katsura Ito, Yamanashi, JP;
Kenji Koushiro, Yamanashi, JP;
Pioneer Electronic Corp., Yamanashi, JP;
Abstract
A method for preparing a stamper comprises the steps of forming a first electro-conductive layer and a second electro-conductive layer on a photoresist layer carrying pits through a physical vapor deposition before the electroforming of a stamper layer. The second electro-conductive layer is effective for preventing the first electro-conductive layer from corroding during the electroforming step because of the active treatment solution for the electroforming and also avoids the corrosion of the first electro-conductive layer even in the storage period before the particular electroforming step.