EXPOSURE SYSTEM AND EXPOSURE METHOD

摘要

An exposure apparatus able to maintain reflectance of mirrors and transmittances of lenses and to maintain initial performance over a long period by using exposure light of a wavelength of the vacuum ultraviolet region to illuminate a mask (27) and transfer images of patterns on the mask (27) to a substrate (37), provided with a gas feed unit (23 to 26 and 69 to 72) for supplying a light path space through which the exposure light passes with a gas mainly comprised of an inert gas or rare gas and introducing a predetermined concentration of hydrogen into the gas fed to at least part of the light path space. <IMAGE>