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. 12, 2002
Filed:
Mar. 03, 2000
Akira Fujinoki, Koriyama, JP;
Takayuki Oshima, Koriyama, JP;
Hiroyuki Nishimura, Koriyama, JP;
Yasuyuki Yaginuma, Koriyama, JP;
Other;
Abstract
A synthetic glass member for use in excimer laser lithography, having superior homogeneity, high transmittance for ArF excimer laser beams and an excellent resistance against lasers is made from high purity synthetic quartz glass, and it is characterized in that layered structures, striae in three directions and internal strains are thermally and mechanically removed, the distribution of refractive index (&Dgr;n) in a plane orthogonal to the optical axis is up to about 1×10 , the distribution of refractive index (&Dgr;n) in a plane parallel to the optical axis is up to about 5×10 , the birefringence is up to about 2 nm/cm, the hydrogen molecule concentration is at least about 2×10 molecules/cm , and the internal transmittance is at least about 99.8% at a wavelength of 193.4 nm.