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. 02, 2003
Filed:
Nov. 27, 2001
Nikon Corporation, Tokyo, JP;
Abstract
A photolithography apparatus has an exposure light source for emitting exposure light with a wavelength of 400 nm or less, a reticle with a pattern original image formed therein, an illumination optical system for illuminating the reticle with exposure light, a projection optical system for projecting the pattern image from the reticle onto a photosensitive plate and an alignment system for aligning the reticle and the photosensitive plate. At least some of the synthetic silica glass members composing the illumination optical system, the projection optical system and the reticle consist of synthetic silica glass members which, upon 1×10 pulse irradiation with an ArF excimer laser at an energy density from 0.1 &mgr;J/cm ·p to 200 mJ/cm ·p, have a loss factor no greater than 0.0050 cm at 193.4 nm measured after irradiation, a hydrogen molecule concentration from 1×10 molecules/cm to 2×10 molecules/cm and a loss factor no greater than 0.0020 cm before ultraviolet irradiation.