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US 2003/0171203 A1Published application
Quartz glass member and projection aligner
AssigneeNikon Corporation
InventorsNorio Komine, Akiko Yoshida, Hiroki Jinbo, Seishi Fujiwara
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AssigneeNikon Corporation
InventorsNorio Komine, Akiko Yoshida, Hiroki Jinbo, Seishi Fujiwara
Estimating the term…
A silica glass member of the present invention is one wherein when a composition thereof is expressed by SiOx, x is not less than 1.85 nor more than 1.95, wherein a concentration of hydrogen molecules included therein is not less than 1×1016 molecules/cm3 nor more than 5×1018 molecules/cm3, and wherein a difference A−B between an absorption coefficient A immediately before an end of irradiation with 1×104 pulses of ArF excimer laser light in an average one-pulse energy density of 2 mJ/cm2 and a second absorption coefficient B at 600 seconds after a stop of the irradiation with the ArF excimer laser light is not more than 0.002 cm−1. When this silica glass member is applied to an illumination optical system and/or a projection optical system in projection exposure apparatus, it becomes feasible to implement uniform exposure while reducing variation in illuminance on a reticle surface and in an exposure area on a wafer.
A silica glass member wherein when a composition thereof is expressed by SiOx, x is not less than 1.85 nor more than 1.95, wherein a concentration of hydrogen molecules included therein is not less than 1×1016 molecules/cm3 nor more than 5×1018 molecules/cm3, and wherein a difference A−B between an absorption coefficient A immediately before an end of irradiation with 1×104 pulses of ArF excimer laser light in an average one-pulse energy density of 2 mJ/cm2 and an absorption coefficient B at 600 seconds after a stop of the irradiation with the ArF excimer laser light is not more than 0.005 cm−1.
A projection exposure apparatus comprising a reticle having a pattern;
Dependencies are inferred from the claim text.