Secondary electron yield measurements of carbon covered multilayer optics

Share/Save/Bookmark

Chen, Juequan and Louis, Eric and Verhoeven, Jan and Harmsen, Rob and Lee, Chris J. and Lubomska, Monika and Kampen, Maarten van and Schaik, Willem van and Bijkerk, Fred (2010) Secondary electron yield measurements of carbon covered multilayer optics. Applied Surface Science, 257 (2). pp. 354-361. ISSN 0169-4332

[img] PDF
Restricted to UT campus only
: Request a copy
501kB
Abstract:Carbon contamination on extreme ultraviolet (EUV) optics has been observed in EUV lithography. In this paper, we performed in situ monitoring of the build-up and removal of carbon contamination on Mo/Si EUV multilayers by measuring the secondary electron yield as a function of primary electron energy. An electron beam with an energy of 2 keV was used to simulate the EUV radiation induced carbon contamination. For a clean EUV multilayer, the maximum secondary electron yield is about 1.5 electrons per primary electron at a primary electron energy of 467 eV. The maximum yield reduced to about 1.05 at a primary electron energy of 322 eV when the surface was covered by a non-uniform carbon layer with a maximum thickness of 7.7 nm. By analyzing the change in the maximum secondary electron yield with the final carbon layer thickness, the limit of detection was estimated to be less than 0.1 nm.

Item Type:Article
Copyright:© 2010 Elsevier B.V
Faculty:
Science and Technology (TNW)
Research Group:
Link to this item:http://purl.utwente.nl/publications/75235
Official URL:http://dx.doi.org/10.1016/j.apsusc.2010.06.075
Export this item as:BibTeX
EndNote
HTML Citation
Reference Manager

 

Repository Staff Only: item control page

Metis ID: 270287