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:
Mar. 20, 2007
Filed:
Dec. 14, 2004
Seiya Miura, Tochigi, JP;
Seiya Miura, Tochigi, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An exposure apparatus includes a projection optical system for projecting a pattern on a reticle mounted on a first stage onto an object mounted on a second stage, a first reference plate provided on the reticle or a surface equivalent to the reticle, the first reference plate having three or more first reference marks each of which serves as a reference for an alignment between the reticle and the object, a measuring unit for measuring focus position at imaging positions of the first reference marks and for measuring an image surface of the projection optical system, and a correcting unit for correcting a relationship between the image surface and a reference surface as a reference of a measurement by the measuring unit.