Optical apparatus for conditioning a radiation beam for use by an object, lithography apparatus and method of manufacturing devices

摘要

In an EUV (extreme ultraviolet) lithography apparatus, an illumination system includes a multifaceted field mirror and a multifaceted pupil mirror. A field facet mirror within mirror focuses EUV radiation onto a particular associated pupil facet mirror, from where it is directed to a target area. Each field facet mirror is modified to scatter unwanted DUV (deep ultraviolet) radiation into a range of directions. The majority of DUV falls onto neighboring pupil facet mirrors within the pupil mirrors, so that the amount of DUV radiation reaching target E is suppressed in comparison to the wanted EUV radiation. Because the distance between mirrors is much greater than the width of an individual pupil facet mirror, good DUV suppression can be achieved with only a narrow scattering angle. Absorption of EUV radiation in the scattering layer can be minimized.

主权项

1. An optical apparatus comprising:
a first reflective component comprising a primary reflective element and configured to reflect a radiation beam from a radiation source toward a second reflective component; the second reflective component comprising an array of secondary reflective elements and configured to reflect the radiation beam to a target location, wherein:
the radiation beam comprises a first beam having a first wavelength range and a second beam having a second wavelength range;an orientation of the primary reflective element is controllable so as to reflect the first beam toward an associated secondary reflective element or toward one of a subset of associated secondary reflective elements at different times during use; andthe primary reflective element scatters the second beam such that it is directed toward the second reflective component, but not toward the associated secondary reflective element or toward the subset of associated secondary reflective elements.