A new dynamic-XPS end-station for beamline P04 at PETRA III/DESY

ROM 2015-03
Author: Sergey V.Babenkov (1), sergey.babenkov@desy.de
Publication: http://www.sciencedirect.com/science/article/pii/S0168900214015216
Instrument: Argus

Photoelectron spectroscopy is a well-established and commonly used technique to obtain information about electronic structure of solid state materials and rare gases. Recent technical progress in construction of X-Ray sources and detectors provides a possibility to investigate more complex and advanced materials. In order to realize the dynamic-XPS experiments with sufficient energy- and time-resolution, in collaboration with Omicron we have designed and constructed the end station, based on a hemispherical electron spectrometer Argus. The spectrometer is equipped with high speed detection system, which in combination with the high brilliance XUV beamline P04 at PETRA III provides users at PETRA III a unique tool for fast (down to 0.001 s/spectrum) and detailed (energy resolution down to 30 meV) investigations in wide range of photon energies (50 – 3000 eV) compared to existing XPS devices at other beamlines.

The combination of beam line and end station allows to measure dynamic-XPS spectra as a function of varying conditions applied to the sample, using both scanning and snapshot mode, with possibility to parallel snapshot measurements of several core levels. Consequently, it opens access to real time investigations of fast flow processes and quantitative analysis of surface layers. For instance, one can follow the reaction kinetics by observation of spectrum shape or control of the deposition rate and amount of a given substance by monitoring the intensity ratio of peaks in the snapshot spectra. The shown results proof efficiency of the dynamic-XPS end station and the ability to identify critical phases of a fast real time processes by following the evolution of photoemission core level spectra. Since the beamline has a possibility to smoothly change a photon energy and several polarization mode, a NEXAFS and XMSD techniques are available.

In our publication we report on design and performance of new dynamic-XPS end-station as well as on a first time resolved in-situ observation of temperature stimulated graphene growth onto the surface of cubic-SiC/Si wafer.

Sergey V.Babenkov a,n, Victor Y.Aristov b,c, Olga V.Molodtsova a, Konrad Winkler d, Leif Glaser a, Ivan Shevchuk a, FrankScholz a, Jörn Seltmann a, Jens Viefhaus a

a) Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany

b) Institute of Solid State Physics of Russian Academy of Sciences, Chernogolovka 142432, Russia  // http://www.issp.ac.ru/engl/

c) Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, D-20355Hamburg, Germany  //  http://www.uni-hamburg.de/index_e.html

d) Omicron NanoTechnology GmbH, Limburgerstr.75, 65232 Taunusstein, Germany  // www.scientaomicron.com