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. 07, 1999
Filed:
Nov. 04, 1996
Masamitsu Yanagihara, Zama, JP;
Kei Hara, Yokohama, JP;
Seiji Miyazaki, Yokohama, JP;
Hideki Koitabashi, Tokyo, JP;
Yoichi Hamashima, Chiba, JP;
Hiroshi Kitano, Kawasaki, JP;
Yoshiyuki Katamata, Tokyo, JP;
Nikon Corporation, Tokyo, JP;
Abstract
Positional discrepancies of images of segmental areas, which are caused by stretching of a substrate in the Y direction, are corrected by changing magnifications of respective projection optical systems and inclinations of parallel plane glass pieces with respect optical axes. After that, positional discrepancies of the images after the correction are accurately detected by using a calibration system for the projection optical systems. Thus it is possible to confirm whether or not the positional discrepancies are accurately corrected. If the correction is insufficient as a result of the confirmation, at least one of correction of the magnifications of the respective projection optical systems and shift of the images projected through the respective projection optical systems onto the substrate is executed again so that amounts of the positional discrepancies are sufficiently small. On the other hand, the positional discrepancy can be easily determined by storing positional information and a detected signal concerning an image formed by a projection optical system in synchronization with a clock, followed by signal processing.