182
doi:10.1017/S1431927618013260
Microsc. Microanal. 24 (Suppl 2), 2018
© Microscopy Society of America 2018
1D-Full Field Microscopy of Elastic and Inelastic Scattering with Transmission off-
axis Fresnel Zone Plates
F. Döring
1*
, F. Marschall
1
, Z. Yin
2,4
, B. Rösner
1
, M. Beye
2
, P. Miedema
2
, K. Kubiček
2
, L. Glaser
2
,
D. Raiser
4
, J. Soltau
3
, V.A. Guzenko
1
, J. Viefhaus
2
, J. Buck
2
, M. Risch
3
, S. Techert
2, 3, 4
and C. David
1
1.
Paul Scherrer Institut, Villigen-PSI, 5232, Switzerland
2.
Deutsches Elektronen-Synchrotron DESY, Photon Science, Hamburg, 22607, Germany
3.
Georg-August-Universität, Göttingen, 37077, Germany
4.
Max Planck Institute for Biophysical Chemistry, Göttingen, 37077, Germany
* Corresponding author, florian.doering@psi.ch
Resonant inelastic X-ray scattering (RIXS) is a powerful X-ray spectroscopy technique capable of
investigating electronic properties of materials and molecules. Using soft X-rays, it becomes especially
sensitive to the electronic structure of matter due to sharp transitions [1]. Combining this successful
technique with imaging opens up a variety of new possibilities for sample characterization because
electronic information can be obtained with spatial resolution. This allows for investigations of
inhomogeneous materials including interfaces and defects.
Conventional RIXS instrumentation relies on reflecting gratings for analyzing the emitted light from the
sample by dispersing it across a detector. For RIXS imaging this requires a time-consuming point by
point raster scan of the sample in order to finally obtain a complete image of the sample with the
corresponding spectroscopic information [2]. We report on the use of a new zone plate based RIXS
analyzer scheme, which has already been successfully tested for RIXS imaging [3]. An off axis part of a
Fresnel zone plate (FZP) is used as analyzer and replaces the conventional reflection grating. This setup
exploits the fundamental advantage of an X-ray optic that has imaging capabilities. While dispersing the
emitted light across one axis of the detector, it acts as a focusing element for the other axis, making it
possible to combine 1D microscopy with spectroscopy (e.g. RIXS). Moreover and in contrast to point by
point scans (necessary for conventional RIXS setups), line by line scans allow for a much higher
throughput.
This concept was applied to a Siemens star test sample with 500 μm diameter made from SiO
2
on an
iridium-coated silicon substrate. The sample was scanned in 82 steps using a 1 mm long x-ray line focus
having a width of down to 10 μm and a photon energy of around 550 eV. At each step, a line of the
sample was imaged onto the detector and its corresponding energy dispersion was recorded (Fig. 1a).
Here, the zone plate analyzer was focused on the elastic line of the emission ensuring that this will give
a sharp detector image. Combining these 82 slices of the sharp elastic line allows for reconstructing the
RIXS image of the Siemens Star test pattern (Fig. 1b).
The upgrade of this analyzer scheme in terms of instrumentation was the parallel usage of a second off
axis FZP, which makes it possible to focus a second energy from the sample to the detector. The second
FZP can be moved individually from the first one, which allows for two-color spectroscopy combined
with imaging. Here, contributions of two different emitted X-ray energies produce a sharp image on the
detector. This scheme, which is sketched in Fig 2, was successfully implemented and tested at the P04
beamline at PETRA III (DESY). With this advanced analyzer scheme, not only elastic and inelastic
scattering information at two energies can be detected but also two times the solid angle of radiation is
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