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Title: Reflective optical imaging system

An optical system compatible with short wavelength (extreme ultraviolet) radiation comprising four reflective elements for projecting a mask image onto a substrate. The four optical elements are characterized in order from object to image as convex, concave, convex and concave mirrors. The optical system is particularly suited for step and scan lithography methods. The invention increases the slit dimensions associated with ringfield scanning optics, improves wafer throughput and allows higher semiconductor device density.
  1. (Fairfield, CT)
Publication Date:
OSTI Identifier:
Report Number(s):
US 6014252
DOE Contract Number:
Resource Type:
Research Org:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Country of Publication:
United States
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