SYNTHETIC QUARTZ GLASS

摘要

A synthetic quartz glass for use in a unit using ultraviolet rays of 150 to 190 nm wavelength as a light source, which is excellent in resistance to ultraviolet rays of 150 to 190 nm wavelength. A synthetic quartz glass used for rays of 150 to 200 nm wavelength, characterized in that in the synthetic quartz glass, the concentration of OH groups is less than 1 ppm, the concentration of oxygen excess type defects is 1 x 10<16> defects/cm<3> or less, the concentration of hydrogen molecules is less than 1 x 10<17> molecules/cm<3>, and the concentration of noncrosslinked oxygen radicals, exhibited after 3 kJ/cm<2> irradiation with xenon excimer lamp light at an illumination intensity of 10 mW/cm<2> or after 10<7> pulse irradiation with F<2> laser beams at an energy density of 10 mJ/cm<2>/pulse, is 1 x 10<16> radicals/cm<3> or less.