FACETED EUV OPTICAL ELEMENT

摘要

A reflective EUV optic such as a collector mirror configured as an array of facets that are spaced apart to form respective gaps between adjacent facets. The gaps are used as inlets for gas flow across one of the facets such that flow is introduced parallel to the optic surface. The facets can be made with offsets such that loss of reflective area of the EUV optic can be minimized. The gas facilitates removal of target material from the surface of the facets.

主权项

1. A reflective EUV optic comprising:
a first facet comprising a first portion of a reflective surface of the reflective EUV optic; and a second facet comprising a second portion of the reflective surface of the reflective EUV optic, the first facet being separated from the second facet in a direction parallel to an optical axis of the reflective EUV optic and the first facet overlapping the second facet in a direction substantially tangential to the reflective surface to form a gap between the first facet and the second facet.