In recent years, technological developments in the area of extreme ultraviolet
lithography (EUVL) have experienced great improvements. Currently, the application
of EUV radiation apart from microlithography comes more and more into focus.
Main goal of our research is to utilize the unique interaction between soft x-ray
radiation and matter for probing, modifying, and structuring solid surfaces.
In this contribution we present a setup capable of generating and focusing EUV
radiation. It consists of a table-top laser-produced plasma source. In order to obtain a
small focal spot resulting in high EUV fluence, a modified Schwarzschild objective
consisting of two spherical mirrors with Mo/Si multilayer coatings is adapted to this
source, simultaneously blocking unwanted out-of-band radiation. By demagnified
(10x) imaging of the plasma an EUV spot of 5 μm diameter with a maximum energy
density of ~0.72 J/cm² is generated (pulse length 8.8 ns).
We present first applications of this integrated source and optics system,
demonstrating its potential for high-resolution modification and structuring of solid
surfaces. As an example, etch rates for PMMA, PC and PTFE depending on EUV
fluences were determined, indicating a linear etch behavior for lower energy
In order to investigate changes of the chemical composition of PMMA induced by
EUV radiation we present FTIR and NEXAFS measurements on irradiated samples.
The latter were performed using the laboratory source tuned to the XUV spectral
range around the carbon K-edge (λ ~ 4.4 nm) and a flat-field spectrometer.
For showing the potential of this setup, first damage tests were performed on grazing
incidence gold mirrors. For these thin Gold films, threshold energy densities could be
determined, scaling linear with the film thickness.