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:
Nov. 18, 2003
Filed:
Dec. 28, 2001
Akihiro Nakauchi, Tochigi, JP;
Ryuichi Sato, Tochigi, JP;
Canon Kabushi Kaisha, Tokyo, JP;
Abstract
A measurement method of measuring wavefront aberration of a projection optical system in a projection exposure apparatus for projecting a reticle pattern onto a substrate via the projection optical system. The method includes a measurement step of measuring intensity of a light beam having passed through the projection optical system and a phase shift pattern at a plane conjugate to a pupil plane of the projection optical system or a plane spaced apart from the phase shift pattern enough to separately detect respective rays emerging from plural points of the pupil plane, when the phase shift pattern set near an image plane or object plane of the projection optical system for forming an image of a pattern is scanned in one or a plurality of directions perpendicular to an optical axis of the projection optical system. The method also includes a signal processing step of calculating the wavefront aberration of the projection optical system on the basis of a measurement result of the measurement step.