Deutsche Tagung f ¨ur Forschung mit ... - SNI-Portal

Mikroskopie und Tomographie Poster: Mi., 14:00–16:30 M-P111
Applications in hard X-ray mapping and imaging at ANKA using planar
sets of refractive crossed linear lenses from SU-8 polymer
Rolf Simon 1 , Vladimir Nazmov 2 , Elena Reznikova 2 , Jürgen Mohr 2 , Silvia
Diabaté 3 , Volker Saile 2
1 Institut für Synchrotronstrahlung, Forschungszentrum Karlsruhe, Postfach 3640
DE-76021 Karlsruhe – 2 Institut für Mikrostrukturtechnik, Forschungszentrum Karlsruhe,
Postfach 3640 DE-76021 Karlsruhe – 3 Institut für Toxikologie und Genetik,
Forschungszentrum Karlsruhe, Postfach 3640 DE-76021 Karlsruhe
Refractive planar X-ray lenses with linear parabolic profiles are fabricated from SU-8
polymer by direct deep X-ray lithography at the IMT beamlines of the ANKA storage
ring at Forschungszentrum Karlsruhe. The lenses are usually arranged in crossed configuration
for focussing in two directions and in several sets on a single support wafer
in order to cover a wide energy range, e.g. from 5-30 keV. At the ANKA FLUO-TOPO
beam line these lenses frequently have been tested and characterized[1,2], and furthermore
they are regularly used for scanning and mapping applications using micrometer
sized probe beams or full-field imaging applications.
For scanning applications a probe beam size down to 500 nm FWHM could be realized
employing a source demagnification by a factor of approx. 400. With this micro probe
x-ray fluorescence mapping in two and three dimensions was applied to samples like
environmental particles, bones and biological tissue, the excitation energies ranged
between 5 and 28 keV.
For applications in x-ray microscopy using absorption or phase contrast the x-ray lens
was placed behind the micro- and nanoscaled objects in order to form an x-ray image
on the recording CCD camera. The measured resolution of the images was 400±50 nm
that corresponded to the projection optical scheme with 18 mm focal distance of the
lens 30 m remote from the source. The sensitivity of the imaging set-up to even low
phase contrast (≈ 0.065) is demonstrated by visualizing details in human lungs cells
with magnification of 50.