1. Institute of Semiconductor Technology (IHT), Technische Universität Braunschweig, Hans-Sommer-Straße 66, D-38106 Braunschweig, Germany
2. Laboratory for Emerging Nanometrology (LENA), Technische Universität Braunschweig, Langer Kamp 6a, D-38106 Braunschweig, Germany
3. MIND-IN2UB, Department of Electronic and Biomedical Engineering, Universitat de Barcelona, C/Martí i Franquès 1, E-08028 Barcelona, Spain