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2003
Book Article
Title
Methology to evaluate light scatter mechanisms of VUV substrates and coatings
Abstract
Methods for evaluating the quality of CaF2 and SiO2 substrates for deep-ultraviolet (DUV) and vacuum-ultraviolet (VUV) low loss optical components are presented. Today even superpolished CaF2 is available. However, major differences mights till occur between batches and careful control is therefore necessary. By using roughness data from AFM measurements combined with scattering measurements at 19 3 nm and. 157 nm surface roughness as well as in inhomogeneities in the bulk of the material can be studied. Results are also presented of anti-reflective (AR) and highly reflective (HR) multilayer coatings on CaF2 where reduced total back scatter scattering was found for the AR-coating as compared to the substrate.