The generation and investigation of nanostructures on surfaces is in the center of my current research activities. In my working group we follow different routes to fabricate tailor-made nanoscaled structures.
The first (bottom-up) approach is based on the self-assembly of molecules or atoms on surfaces. In this context the geometric and electronic structure of porphyrin derivatives as prototype examples for functional molecules has been intensively studied on different substrates.
In our second (top-down) approach a highly focused electron beam is used to locally dissociate adsorbed precursor molecules (electron beam induced deposition, EBID) or to directly modify the properties of the substrate (electron beam induced surface activation, EBISA) with lithographical control. For both projects we target the understanding of the fundamental physical and chemical processes on an atomic level based on microscopic and spectromicroscopic investigations. Our main methods are scanning tunneling microscopy and spectroscopy, scanning electron microscopy, local Auger electron spectroscopy and atomic force microscopy in an ultra high vacuum environment.
In the future we will target the combination of the two projects described above. Structures fabricated with the electron beam techniques will serve as templates for the local anchoring and/or functionalization of large organic molecules, i.e. in particular porphyrins.
Other future research activities will include:
- further investigation of fundamental aspects of electron induced processes
- instrumental development of EBID attachments to further explore in particular the lithographic process
- further exploration to switch the conformation of certain molecules at or close to room temperature