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:
Dec. 19, 2000
Filed:
Nov. 25, 1997
Katsuhiko Hieda, Yokohama, JP;
Thomas Fischer, Mechanicsville, VA (US);
Andreas Grassmann, Bad Abbach, DE;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Siemens Microelectronics, Inc., Cupertino, CA (US);
Abstract
A shading film of chrome is formed entirely on one surface of a circular substrate of quartz. The substrate is rotated and resist is applied to the shading film. Since the substrate is shaped in a circle, the resist spreads uniformly on the entire surface of the shading film by the centrifugal force. Therefore, the resist has a substantially uniform film thickness over almost the entire surface of the shading film. This resist is patterned to form a resist pattern. By etching the shading film with the resist pattern used as a mask, a pattern preferable in accuracy of dimensions can be formed.