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As a consequence of the steadily increasing EUV powers and radiation doses, damage and degradation testing of EUV
optical elements has become an important issue. In this contribution we report on first damage tests on optics and
detectors for the wavelength of 13.5nm using a high fluence micro-focus from a laboratory-scale EUV source. The setup
consists of a laser-generated plasma from a pulsed gaseous Xenon jet or a solid Au target, respectively. In order to obtain
a small focal spot resulting in a high EUV fluence, a modified Schwarzschild objective consisting of two spherical
mirrors with Mo/Si multilayer coatings is adapted to the source, simultaneously blocking unwanted out-of-band
radiation. By demagnified (10x) imaging of the Au plasma an EUV spot of 5 μm diameter with a maximum energy
density of ~1.3 J/cm2 is generated at a wavelength of 13.5 nm and a pulse width of 8.8 ns.
We demonstrate the potential of this integrated source and optics system for damage testing on EUV optical elements
and sensoric devices. As an example, single pulse ("1-on-1") and multiple pulse ("S-on-1") damage thresholds were
determined for Mo/Si multilayer mirrors, using both on-line optical microscopy, interferometry and atomic force
microscopy for damage detection. The data are compared with in-situ measurements of the reflectivity change at 13.5nm.
Moreover, thin metal coatings (Gold) used as grazing incidence mirrors were irradiated. Threshold energy densities for
damage and film removal were determined, showing a linear dependence on the film thickness. Furthermore, EUV-to-VIS quantum convertors (Ce:YAG crystals, phosphor coatings) employed for beam characterization were investigated in
terms of linearity, saturation behavior and conversion efficiency.
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