Exposure apparatus with irradiation device for irradiating optical element with pulsed light having infrared wavelength, and corresponding exposure method

摘要

The present invention provides an exposure apparatus for exposing a shot on a substrate to first pulsed light, the apparatus including an optical element for guiding the first pulsed light to the substrate, an irradiation device configured to irradiate the optical element with second pulsed light having an infrared wavelength which the first pulsed light has less than the second pulsed light has, and a controller configured to control the irradiation device in a process of exposing the shot to the first pulsed light plural times, such that the irradiation device irradiates the optical element with the second pulsed light during at least one period of non-irradiation periods in which the shot is not irradiated with the first pulsed light.