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. 30, 2003
Filed:
Sep. 18, 2000
Chih-Kung Chang, Hsin-Chu, TW;
Bii-Jung Chang, Hsin-Chu, TW;
Sheng-Liang Pang, Hsin-Chu, TW;
Kuo-Liang Lu, Hsin-Chu, TW;
Taiwan Semiconductor Manufacturing Company, Hsin-chu, TW;
Abstract
Pigment-based resists tend to give off a certain amount of organic vapor during exposure. This brings about contamination of the projection lens surface as well as other parts of the system. A method to monitor this accumulation of solvent vapor on the lens surface is disclosed, based on a test matrix (in which exposure time and focal distance are systematically varied) through which a series of images are formed in the resist and then evaluated for quality. A key feature is the test patterns that are used for forming the images. Said patterns are designed so as to maximize the total amount of diffraction that occurs during image formation, thereby maximizing sensitivity to changes in lens quality. Several examples of the test patterns are provided.