1. Institute for Experimental Physics II, Application Oriented Plasma Physics; Ruhr-Universität Bochum; Universitätsstraße 150 44801 Bochum Germany
2. Institute of Plastics Processing; RWTH Aachen University; Pontstraße 49 52062 Aachen Germany
3. Institute for Materials, Chair for MEMS Materials; Ruhr-Universität Bochum; Universitätsstraße 150 44801 Bochum Germany