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. 12, 2000
Filed:
Mar. 24, 1997
Nobuyuki Irie, Kawasaki, JP;
Nobutaka Magome, Kawasaki, JP;
Yasuaki Tanaka, Chigasaki, JP;
Naomasa Shiraishi, Kawasaki, JP;
Shigeru Hirukawa, Kashiwa, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A projection exposure apparatus which can perform superior observation or projection of a selected mark when the mark is observed or projected through a projection optical system in which a pupil filter is set. The projection exposure apparatus which projects a pattern on a mask through a projection optical system onto a photosensitive substrate held on a substrate stage movable in a plane perpendicular to the optical axis of the projection optical system and which has a pupil filter (optical correction plate) placed on or near the pupil plane of the projection optical system, a reference mark formed on the substrate stage in a scale factor according to the shape of the pupil filter, illuminating means for illuminating the reference mark with illumination light, and light-receiving means for receiving the illumination light having emerged from the reference mark and thereafter having passed the projection optical system.