| 摘要 |
An exposure apparatus includes an illumination optical system configured to illuminate a mask with a laser beam having a wavelength shorter than 250 nm, 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 satisfying either grade 1 or grade 2 (Japan Optical Glass Industry Society Standard), an absorption coefficient α at 3585 cm−1 equal to or below 0.035/cm, and the content of aluminum and lithium being equal to or below 1 and 0.5 ppm, respectively.
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