Nanomaterials and transport
We develop techniques to electronically contact single organic molecules. Electrical current transport through single molecules has been actively investigated during the past years, because they promise new possibilities for scaling down sizes of electronic circuits. A technique for reliable fabrication of single molecule contacts, however, could not be demonstrated so far. Using electron beam lithography (EBL) in combination with etching techniques we developed several such contacting techniques and use them for the electrical characterization for various molecules. Thus, we understand the electrical behavior of single molecular electronic building blocks and can use this knowledge for the development of real molecular electronic circuits. This topic is closely linked to the Research School NanoNet.
Nanomechanical resonators can be used for example as detectors or mechanical switches. Therefore these structures offer new possibilities in generating nanoscale electrical circuits as well. The damping behavior of such structures is not well understood. The goal of our experiments is therefore to use advanced structuring methods and modern materials to investigate the damping mechanisms in nanomechanical resonators.
Our thin-film research focuses on the development of solar selective coatings for solar thermal power plants with the aim of high solar selectivity and high temperature stability. They could be used in the next generation of solar power plants contributing to help manage the energy transition. Another area of application-relevant research is dry-lubricant coatings, which are important in the context of sustainable energy and material use.
Magnetic multilayers are defined by molecular beam epitaxy (MBE) and structured by EBL. These devices which can have smallest structures as small as 10 nm are electrically characterised. They are central to the development of high density memory elements. We study the switching behaviour of nanoscopic magnets and the excitations associated which such mechanisms. Colloidal model systems help us to understand magnetic interactions in general.
The Nanofabrication Facility in Rossendorf (NanoFaRo) is serving a large number of internal and external users (currently around 40) running a vast variety of projects. We amassed extensive experience in high-resolution patterning (down to 6-7 nm) of the main semiconductor substrate materials such as silicon (Si) and silicon-on-insulator (SOI) for nanoelectronics and photonics applications as well as of a wide range of magnetic materials for spintronics, magnonics, etc. applications. Central to our activities is the high-precision contacting of nanostructures randomly distributed on a wafer surface such as bottom-up grown nanowires, DNA origami, flakes of 2D materials, etc.
We operate two EBL systems, Raith 150 Two and Raith e_LiNE plus (Raith GmbH), using different positive and negative resists.
For thin film deposition we use mainly two evaporation machines: UHV evaporation tool BETty (BESTEC GmbH) and LAB 500 evaporation tool (Leybold Optics GmbH), both equipped with electron beam and thermal evaporators, as well as a sputter system NORDIKO 2000 (NORDIKO Ltd.) equipped with 4 magnetrons: 2 operating in DC-mode and 2 operating in DC- or RF-mode.
More information here.