Dresden 2011 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
DS: Fachverband Dünne Schichten
DS 65: Organic Thin Films IV
DS 65.5: Talk
Friday, March 18, 2011, 17:00–17:15, GER 38
Coupling effects in mixed pentacene/perfluoropentacene thin films studied by Raman and photoluminescence spectroscopy — •Falk Anger1,2, J. Oriol Ossó2, Ute Heinemeyer1, Katharina Broch1, Reinhard Scholz3, Alexander Gerlach1, and Frank Schreiber1 — 1Institut fur Angewandte Physik, 72076 Tübingen — 2Matgas 2000 AIE, Campus de la UAB, 08193 Bellaterra, Spain — 3Walter Schottky Institut, TU München, 85748 Garching
One of the crucial issues in complex organic electronic device structures is the coupling between
different organic components. Perfluoropentacene (PFP) and pentacene (PEN) form a donor-acceptor system and are expected to promote intermixing due to their structural similarity, which also raises the chance of spectral coupling [1, 2].
Blended PEN/PFP thin films (ratio 4:1, 1:1, and 1:2) are investigated by photoluminescence (PL) and resonant Raman spectroscopy using different wavelengths covering the main absorption features of pure and mixed films. The results point towards substantial coupling between the two components. Contrary to pure PEN and PFP, the mixtures reveal at low temperatures a pronounced PL-peak at around 1.4 eV.
Raman spectroscopy shows a dependence of the strength of PEN and PFP peaks on the mixing ratio and the excitation wavelength. While both PEN and PFP peaks are observed for excitation at 488 nm and 514 nm, at 633 nm the strength of vibrational modes depends drastically on the mixing ratio.
[1] A. Hinderhofer et al., J. Chem. Phys. 127, 194705 (2007)
[2] K. Broch et al. submitted