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. 16, 2003
Filed:
Mar. 30, 2001
Michio Kohno, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
Disclosed is an exposure method, an exposure apparatus and a device manufacturing method, in which transmission factors of almost all optical systems, including a projection optical system, can be measured during an exposure process, and in which the exposure amount is controlled on the basis of it. The exposure apparatus includes an illumination optical system for illuminating a pattern of a reticle with a laser beam from an excimer laser, and a projection lens system for projecting the pattern illuminated by the illumination optical system onto a wafer, to thereby expose the wafer with the reticle pattern, wherein reflection light or ghost light produced at a surface of a lens of the projection lens system is received by a sensor and, on the basis of the an output of the sensor, the transmission factor of the projection lens system is measured. The exposure amount is then controlled on the basis of the measurement.