@inproceedings{a341aeed5dd14b3a915d2cd3f69572e2,
title = "Ellipsometric and surface acoustic wave sensing of carbon contamination on EUV optics",
abstract = "Carbon contamination layers, deposited on extreme ultraviolet (EUV) multilayer mirrors during illumination were characterized ex situ using spectroscopic ellipsometry (SE), laser generated surface acoustic waves (LG-SAW), and by their EUV reflectance loss. We show SE is more sensitive to the deposition of carbon layers than the EUV reflectance loss, even in the presence of the highly heterogeneous structure of the multilayer. SE has better overall sensitivity, with a detection limit of 0.2 nm, while LG-SAW has an approximate detection limit < 5 nm",
keywords = "Spectroscopic ellipsometry, METIS-260100, Extreme ultraviolet lithography, EUV optics, multilayer mirrors, surface acoustic wave, carbon contamination, IR-77749",
author = "Juequan Chen and Eric Louis and Frederik Bijkerk and Lee, {Christopher James} and Herbert Wormeester and Reinhard Kunze and Hagen Schmidt and Dieter Schneider and Roel Moors and {van Schaik}, Willem and Monika Lubomska",
year = "2009",
month = feb,
day = "22",
doi = "10.1117/12.824435",
language = "Undefined",
isbn = "9780819475244",
series = "Proceedings of SPIE",
publisher = "SPIE",
pages = "727140--",
editor = "Schellenberg, {Frank M.} and {La Fontaine}, {Bruno M.}",
booktitle = "Proceedings of SPIE, The International Society for Optical Engineering",
address = "United States",
note = "Alternative Lithographic Technologies ; Conference date: 22-02-2009 Through 27-02-2009",
}