Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

MI: Fachverband Mikrosonden

MI 2: Analytical Electron Microscopy: SEM and TEM-based Material Analysis

MI 2.2: Hauptvortrag

Dienstag, 8. März 2016, 12:00–12:45, H5

Highly spatially resolved cathodoluminescence of III-Nitride based nanostructures directly performed in a Scanning Transmission Electron Microscope at liquid He temperatures — •Juergen Christen, Gordon Schmidt, Frank Bertram, Marcus Mueller, and Peter Veit — Otto-von-Guericke-Universität Magdeburg, Germany

For a detailed understanding of complex semiconductor heterostructures and the physics of devices based on them, a systematic determination and correlation of the structural, chemical, electronic, and optical properties on a nanometer scale is essential. Luminescence techniques belong to the most sensitive, non-destructive methods of semiconductor research. The combination of luminescence spectroscopy - in particular at liquid He temperatures - with the high spatial resolution of a scanning transmission electron microscope (STEM) (dx < 1 nm at RT, dx < 5 nm at 10 K), as realized by the technique of low temperature scanning transmission electron microscopy cathodoluminescence microscopy (STEM-CL), provides a unique, extremely powerful tool for the optical nano-characterization of semiconductors, their heterostructures as well as their interfaces. Typical results, which will be presented, include nm-scale correlation of the optical properties with the crystalline real structure of GaN/AlN quantum dots. In particular, we will show the preferential nucleation of GaN/AlN quantum dots at threading dislocation without inhibition of very sharp emission lines with line width below 0.5 meV.