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:
Sep. 14, 1999
Filed:
May. 26, 1997
Chun-Jen Chen, Chung-Li, TW;
Ming-Hung Su, Yong-Her, TW;
Joseph C-C Hung, Kaohsiung, TW;
James Hsi-Tang Lee, Hsinchu, TW;
Trace Storage Tech. Corp., Hsinchu, TW;
Abstract
A wet etching method for making calibration bump disks for use in providing quality control of production run magnetic hard disks is disclosed. It includes the steps of: (a) coating a layer of bump material on a substrate; (b) coating a photoresist layer on the layer of bump material; (c) exposing the photoresist layer to a light source under a photomask; (d) developing the photoresist layer using a developer solution to form an undeveloped photoresist layer; (e) etching the substrate containing the layer of bump material and the undeveloped photoresist layer to remove portions of the layer of bump material not covered by the undeveloped photoresist layer; and (f) stripping the undeveloped photoresist layer to leave at least a bump on the substrate which was originally covered by the undeveloped photoresist layer. The wet etching method eliminates many of the problems observed from the conventional metal mask method, including the elimination of the convex-shaped bump surface.