1. Nanotechnology Group, Institute for Micro- and Nanoelectroniks, Institute for Micro- and Nanotechnologies MacroNano, Technische Universität Ilmenau, PO Box 100565, 98684 Ilmenau, Germany
2. Department Materials for Electronics, Institute of Materials Science and Engineering, Institute for Micro- and Nanotechnologies MacroNano, Technische Universität Ilmenau, PO Box 100565, 98684 Ilmenau, Germany