Advanced Characterisation Methods (ACM)

(Prof. Dr.-Ing. Gunther Eggeler, Juniorprof. Dr. Tong Li, Dr. rer. nat. Christoph Somsen, Dr.-Ing. Jan Frenzel)

To start off with, the series of lectures reviews important aspects of the atomic configurations in amorphous and crystalline solids. It then considers the interaction of electrons with solids, discussing electron beams and highlighting the significance of secondary electrons, back-scattered electrons, elastically and inelastically scattered electrons and the origin of characteristic Xrays, which are used for chemical analysis in electron microscopy. The physical origin of image contrasts in the scanning and the transmission electron microscope are discussed. Special emphasis is placed on the formation of Kikuchi line diffraction patterns. In scanning electron microscopy, Kickuchi lines are used for all orientation imaging techniques (OIM /EBSD) which allow us to determine the orientation of grains and to establish the presence of textures. In the case of transmission electron microscopy, Kikuchi line diffraction patterns are used as crystallographic maps which allow to orient single crystals. It will be explained how simple two beam diffraction contrasts can be obtained and a brief introduction into stereographic 3D methods in scanning and transmission electron microscopy will be given. All theoretical concepts will be accompanied by practical examples from research projects. The classes are held on Fridays from 3.00 to 6.00 pm.

Lecture Announcement SS 2020