1. CENIMAT|i3N, Department of Materials Science, School of Science and Technology, NOVA University of Lisbon and CEMOP/UNINOVA, Campus de Caparica, Caparica 2829-516, Portugal
2. Department of Physics, CICECO─Aveiro Institute of Materials, University of Aveiro, Campus Universitário de Santiago, Aveiro 3810-193, Portugal
3. Fraunhofer Institute for Solar Energy Systems ISE, Heidenhofstr. 2, Freiburg 79110, Germany
4. Freiburg Material Research Center FMF, University of Freiburg, Stefan-Meier-Str. 21, Freiburg 79104, Germany
5. CHOSE, Department of Electronic Engineering, Università degli Studi di Roma Tor Vergata, Via del Politecnico 1, Rome 00133, Italy