1. Fraunhofer ENAS, Technologie-Campus 3, 09126 Chemnitz, Germany and Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, Germany
2. Center for Microtechnologies, TU Chemnitz, Reichenhainer Str. 70, 09126 Chemnitz, Germany
3. Department of Physics, TU Chemnitz, Reichenhainer Str. 70, 09126 Chemnitz, Germany; Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstraße 400, 01328 Dresden, Germany; and Center for Advancing Electronics Dresden, TU Dresden, 01062 Dresden, Germany
4. Fraunhofer ENAS, Technologie-Campus 3, 09126 Chemnitz, Germany