Electron Probe Microanalyzer

• Subject Area: Materials Science
• Term: Funded in 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 445269564

The requested major instrumentation is an electron probe microanalyzer (EPMA) equipped with a field emission scanning electron microscope, a secondary and a backscattered electron detector, an energy dispersive X-ray (EDS) spectrometer, four wavelength dispersive spectrometers (WDS) and a soft X-ray emission (SXES) spectrometer.This electron probe microanalyzer opens up a new field of research at the Technical University of Dortmund, since it will be possible to quantitatively determine spatially resolved all elements (except hydrogen) with a detection limit of approx. 0.001% during a sample examination and imaging in the electron microscope. The detection of very low element concentrations and the identification of the elements lithium, beryllium and boron and the quantification of the light elements oxygen, nitrogen and carbon will thus be possible for the first time with a spatially resolved sample image in the micro- or nanometer range by the use of wavelength dispersive spectrometers at the TU Dortmund. In addition, the integrated SXES (Soft X-Ray Emission Spectrometer) spectrometer has the advantage of identifying both elements and chemical bonding states, especially in the light element region. Here it worked in the energy range of 50 eV - 210 eV with a very high energy resolution of 0.3 eV (for comparison: WDS: 8 eV, EDS: 130 eV). This combination of spectrometers can be used to identify and analyze spatially resolved interface reactions, diffusion processes, grain boundary precipitations, phase and mixed crystal formations in which elements with very low element concentrations or light elements (lithium, beryllium, boron, carbon, nitrogen, oxygen) on the operations are involved. A spatially resolved detection of borides, carbides, nitrides and oxides, of graphitization effects on diamonds or of chemical bonding states is possible.Therefore, a necessary addition to the previous equipment is the acquisition of this electron probe microanalyzer (EPMA), with which the research questions in the field of quantitative elemental and trace analysis can be clarified. An electron microscope with such an equipment for elemental analysis is not available at the TU Dortmund.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: Elektronenstrahl-Mikrosonde
• Instrumentation Group: 4040 Röntgenmikrosonden
• Applicant Institution: Technische Universität Dortmund
• Leader: Professor Dr.-Ing. Wolfgang Tillmann