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:
Aug. 17, 2004
Filed:
Oct. 15, 2001
Masaru Ogata, Tochigi, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An exposure apparatus for illuminating a reticle with exposing light from an exposing light source via a light-source lens system, and projecting a pattern, which has been formed on the reticle, onto a wafer via a projection lens system, thereby exposing the wafer to the pattern. The apparatus includes vessels for hermetically sealing the light-source lens system and the projection lens system disposed on the optical path of the exposing light from the exposing light source to the reticle, a gas supply unit for supplying the vessels with a specific gas, a vacuum source for evacuating the interior of the vessels, a vacuum-pressure controller for exercising control to hold the internal pressure of the vessels constant, and an escape valve for reducing the differential pressure between the internal pressure of the vessels and atmospheric pressure to a value below a predetermined pressure.