Patents Assigned to Shin-Etsu Quartz Products Company Limited
  • Patent number: 5523266
    Abstract: A synthetic quartz glass optical member for an ultraviolet laser, where the quartz glass has a hydroxyl content of 10-100 ppm, a chlorine content of 200 ppm or less, a hydrogen content of 1.times.10.sup.16 molecules/cm.sup.3 or less, a homogeneity of refractive index of 5.times.10.sup.-6 or less in terms of .DELTA.n, and a birefringence of 5 nm/cm or less.
    Type: Grant
    Filed: August 5, 1994
    Date of Patent: June 4, 1996
    Assignee: Shin-Etsu Quartz Products Company Limited
    Inventors: Hiroyuki Nishimura, Akira Fujinoki, Toshikatsu Matsuya, Kyoichi Inaki, Toshiyuki Kato, Atsushi Shimada
  • Patent number: 5364433
    Abstract: A synthetic quartz glass optical member for an ultraviolet laser, suitably applicable as a stepper lens of a lithographer using an excimer laser beam and other optical members, wherein the quartz glass has a hydroxyl content of 10 to 100 ppm, a chlorine content of 200 ppm or less, a hydrogen content of 1.times.10.sup.16 molecules/cm.sup.3 or less, a homogeneity of refractive index of 5.times.10.sup.-6 or less in terms of .DELTA.n, and a birefringence of 5 nm/cm or less. The optical member can be produced by subjecting a volatile silicon compound to flame hydrolysis with oxyhydrogen flame, depositing the formed particulate silica on a heat-resistant support to prepare a porous silica matrix, heating the matrix in a vacuum as high as 1.times.10.sup.-2 Torr or above to a temperature of 1,400 .degree. C.
    Type: Grant
    Filed: May 15, 1993
    Date of Patent: November 15, 1994
    Assignee: Shin-Etsu Quartz Products Company Limited
    Inventors: Hiroyuki Nishimura, Akira Fujinoki, Toshikatsu Matsuya, Kyoichi Inaki, Toshiyuki Kato, Atsushi Shimada