Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Compact extreme ultraviolet reflectometer for the characterization of grazing incidence optics based on a gas discharge light source

: Bergmann, K.; Rosier, O.; Metzmacher, C.


Review of scientific instruments 76 (2005), No.4, Art. 043104, 5 pp.
ISSN: 0034-6748
ISSN: 1089-7623
Journal Article
Fraunhofer ILT ()

A grazing incidence reflectometer operating in the extreme ultraviolet (EUV) spectral range around 13.5 nm is presented which is making use of a compact xenon pinch plasma light source. The apparatus allows for measuring the absolute reflectivity of a sample for grazing incidence angle in the range from typically 5° to 35° by comparing the EUV diode signal for the reflected light and a reference diode with an accuracy of better than 2%. Design criteria for proper matching of diode apertures and distances with respect to the spatially extended plasma source are presented. The absolute accuracy has been checked by investigating a ruthenium sample with low roughness, which has a reflectivity in the EUV close to the theoretical limit. Comparison to measurements at the EUV-reflectometer of the Physikalisch Technische Bundesanstalt in Berlin at a synchrotron source confirm the absolute accuracy of better than 2% for the reflectivity for the angle interval of interest.