Nikon Corporation

Norihisa Yamaguchi

Hiroki Jinbo

Norio Komine

Seishi Fujiwara

Akiko Yoshida

Kazuhiro Nakagawa

Shouji Yajima

An optical member made of silica glass manufactured by the direct method where a material gas comprising an organosilicon compound is allowed to react in an oxidizing flame, said optical member having a 2&times;10 molecules/cm or less concentration of formyl radical generated by X-ray irradiation whose dose is 0.01 Mrad or more and 1 Mrad or less.

Optical member made of silica glass, method for manufacturing silica glass, and reduction projection exposure apparatus using the optical member

An apparatus is provided for synthesizing a silica glass ingot. The appartus includes a stage having a target plate thereover, the target plate being rotatable relative to the stage around a predetermined vertical axis, and a furnace for reacting material gas with combustion gas to synthesize the silica glass ingot on the target plate; the furnace having an opening at its bottom. The appratus further includes an elevation system that moves the stage in a vertical direction parallel to the predetermined vertical axis so as to vertically move the target plate through the opening of the furnace, the elevation system supporting the stage from at least one side of the stage and lacking a structure directly below the stage that would substantially interfere with the vertical movement of the stage.

Synthetic silica glass manufacturing apparatus

Growing community of inventors

Sagamihara, Japan

Norihisa Yamaguchi