Courses on Advanced Topics III - EELS and CL for chemical and optical quantification in (S)TEM

Presentations from the course were distributed directly to the participants. 

5. - 6. 6. 2019  

at FME, Technická 2, A5 building, seminar room U7   

Dr. Michael Stöger-Pollach  

Vienna University of Technology  
President of the Austrian Society for Electron Microscopy (ASEM)  

Wednesday 5. 6. 

10:00 – 12:00    introduction and elastic electron scattering
An historic overview about the development about electron beam techniques for
chemical analysis is given. The three main analytical techniques in (S)TEM are discussed in general, their fields of application are outlined. Elastic scattering cross sections are calculated and discussed.

lunch break

13:30 – 15:00    inelastic electron scattering I
An introduction into Bethe theory is briefly given as preparation step for the dielectric formalism based on Maxwell’s theory. The Drude and the Drude-Lorentz model are discussed as well as plasmonic excitations in solids and nano-objects.

15:30 – 17:00    inelastic electron scattering II
Kramers-Kronig Analysis and the retrieval of the optical properties are contoured within this lecture. Additionally, radiation losses are investigated and multiple scattering is described. Finally yet importantly, the ionization edge fine structure (ELNES) is discussed

Thursday 6. 6. 

09:00 – 10:30    resolution limits, spatial resolution, and spectrometer designs
The spatial resolution and the resolution limits of inelastic electron scattering techniques are outlined by making use of the Rose-criterion. Finally, several spectrometer designs are discussed in terms of advantages and disadvantages.

11:00 – 12:30    energy filtered TEM and chemical microanalysis in EELS
Energy Filtered TEM (EFTEM) is a widely used technique for fast elemental mapping. Its advantages and disadvantages are discussed, before chemical microanalysis is described. At the end, chemical micro analysis by terms of EFTEM is introduced. 

lunch break

14:00 – 15:30    cathodoluminescence
Cathodoluminescence becomes more and more common, even in a STEM. We discuss the applications and limitations for semiconductors and nano-objects.