Spectral-purity-enhancing layer for multilayer mirrors.
We demonstrate, both theoretically and experimentally, that special spectral-purity-enhancing multilayer mirror systems can be designed and fabricated to substantially reduce the level of out-of-band radiation expected in an extreme ultraviolet lithographic tool. A first proof of principle of applying such spectral-purity-enhancement layers showed reduced out-of-band reflectance by a factor of five, while the in-band reflectance is only 4.5% (absolute) less than for a standard capped multilayer.
van Herpen
M M J W
MM
Philips Research Laboratories, Eindhoven, The Netherlands. maarten.van.herpen@philips.com
van de Kruijs
R W E
RW
Klunder
D J W
DJ
Louis
E
E
Yakshin
A E
AE
van der Westen
S Alonso
SA
Bijkerk
F
F
Banine
V
V