The focus of the work of the Institute of Applied Physics of the TU Bergakademie Freiberg is on the development and the use of tailored functional materials for new devices for the silicon technology, as well as the transfer of this knowledge to new semiconductor materials, such as GaN. In this case, the controlled layer structure and its characterization in nanometer scale play a central role. The generation of zero-, one- and two-dimensional quantum structures in these layers and their functionality repesent a particular challenge.