Synthetic quartz member, exposure apparatus, and method of manufacturing exposure apparatus

摘要

An exposure apparatus includes an illumination optical system configured to illuminate a mask by using a laser beam having a wavelength shorter than 250 nm as a light source, and a projection optical system configured to project and expose a pattern image of the mask onto an exposed substrate, in which an optical element made of a synthetic quartz member is disposed in the illumination optical system and/or the projection optical system. The synthetic quartz member satisfies the following conditions of initial transmittance relative to light having a wavelength of 150 nm being equal to or above 60% per centimeter, striae therein satisfying either grade 1 or grade 2 as defined in Japan Optical Glass Industry Society Standard (JOGIS), an absorption coefficient alpha for an infrared absorption band of a hydroxyl group located at 3585 cm^-1 being equal to or below 0.035/cm, and the content of aluminum being equal to or below 1 ppm while the content of lithium being equal to or below 0.5 ppm.