摘要 |
A protector for a viewport of a vacuum chamber includes a substrate material that absorbs radiation having a wavelength of an amplified light beam and radiation having a wavelength included in an emission spectra of a target material that produces EUV light when ionized by the amplified light beam. The substrate material transmits one or more of visible or near-infrared light. The protector also includes a layer formed on the substrate material, and the layer reflects radiation having the wavelength of the amplified light beam. |