1. Centre for Advanced Photovoltaics, Faculty of Electrical Engineering, Czech Technical University in Prague, Technická 2, 16627 Prague, Czech Republic
2. Institute of Physics, AS CR v. v. i., Prague, Cukrovarnická 10, 16200 Prague, Czech Republic
3. Department of Chemistry and Physics of Surfaces and Biointerfaces, Institute of Macromolecular Chemistry, Czech Academy of Sciences, Heyrovsky sq. 2, 16206 Prague, Czech Republic
4. Institute of Microengineering (IMT), Photovoltaic and Thin-Film Electronics Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), Rue De La Maladière 71b, 2002 Neuchâtel, Switzerland