[1] Catholic Univ Louvain, Unit Phys & Chim Hauts Polymeres, B-1348 Louvain, Belgium
[2] Catholic Univ Louvain, Res Ctr Micro & Nanoscop Mat & Elect Devices, CeRMiN, B-1348 Louvain, Belgium
[3] Catholic Univ Louvain, Unit Chim Mat Inorgan & Organ, B-1348 Louvain, Belgium
[4] Catholic Univ Louvain, Unit Dispositifs Integres & Circuits Elect, B-1348 Louvain, Belgium
[5] Katholieke Univ Leuven, Dept Chem, B-3001 Heverlee, Belgium