1. Bio and Organic Electronics Unit, Department of Smart Hardware, Digital Systems Division, RISE Research Institutes of Sweden AB, 602 21 Norrköping, Sweden
2. Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, 602 21 Norrköping, Sweden
3. Department of Physics, Chemistry and Biology, Linköping University, 581 83 Linköping, Sweden