Physikalisch-Technische Bundesanstalt

The working group X-ray Spectrometry operates a plane grating monochromator (PGM) beamline located at the PTB laboratory at BESSY II. This beamline provides tunable undulator radiation in the photon energy range from 78 eV to 1860 eV. The group's major responsibilities involve both the further methodological development of X-Ray Fluorescence analysis (XRF) and the application-orientated use of reference-free XRF procedures for the investigation of wafer surfaces, micro- and nanolayered systems as well as samples taken from the environment. Two dedicated UHV measuring chambers of different sizes are employed when analyzing wafers (up to 300 mm) and other samples. The smaller measuring chamber can also be used at other beamlines, such as the four-crystal monochromator beamline of the PTB or the BAMline, allowing for higher excitation energies of up to 10 keV or 60 keV respectively.

The further improvement of reference-free X-ray fluorescence analysis and the set-up of high resolution wavelength-dispersive X-ray spectrometry were major tasks in a recent project on applied research in optical technologies together with the German Federal Institute for Materials Research and Testing (BAM) and the Technical University Berlin. A novel method for the non-destructive speciation of buried nanolayers involving Grazing-Incidence XRF and probing the Near Edge X-ray Absorption Fine Structure (NEXAFS) has been developed in cooperation with the Technical University Darmstadt in a basic research project financed by the German Research Foundation (DFG).

Currently the group substantially contributes to the European ANNA project aiming on improved analytical techniques for nano- and microelectronics in dedicated joint research activities dealing with inorganic and organic surface contamination analysis as well as with the characterization of ultra shallow junctions and nanolayers of novel materials.

In another research project, together with the German Federal Institute for Materials Research and Testing (BAM) and Bruker AXS MA, the group is developing reliable XRF characterization methods for the elemental composition of nanoparticles.

The working group has the additional task to establish at the Metrology Light Source (MLS) IR and THz microspectrometry. For this purpose, a typical IR and a dedicated THz beamline are used.