Structure Determination and Electron Microscopy

ABF-STEM-image in atomic resolution of a boundary between w-GaN and c-GaN.

Structural and chemical characterization of materials at the atomic scale is an important prerequisite for understanding the relationships between material structure and material properties. Analytical transmission electron microscopy (TEM) is a powerful tool in material science and allows to link the relationships efficiently. The main research of the group is devoted to study the real structure of thin films, interfaces and nanomaterials by using atomic-resolution scanning TEM and spectroscopy methods in TEM. The TEM investigations are carried out using a probe Cs-corrected Titan3 G2 60-300 analytical TEM equipped with a GIF Quantum and with a Super-X system. In addition, a Hitachi 8100 is used for preliminary TEM studies and a ESEM (Quanta 250) is applied for the investigation of sample surfaces.

Selected Publications

  • A. Lotnyk, D. Poppitz, J.W. Gerlach, B. Rauschenbach, Direct imaging of light elements by annular dark-field aberration-corrected scanning transmission electron microscopy, Appl. Phys. Lett. 104 (2014), 071908.

  • U. Ross, A. Lotnyk, E. Thelander, B. Rauschenbach, Direct imaging of crystal structure and defects in metastable Ge2Sb2Te5 by quantitative aberration-corrected scanning transmission electron microscopy, Appl. Phys. Lett. 104 (2014), 121904.

  • D. Poppitz, A. Lotnyk, J.W. Gerlach, B. Rauschenbach, Microstructure of porous gallium nitride nanowall networks, ACTA MATER 65 (2014), 98-105.