Regensburg 2007 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
DS: Fachverband Dünne Schichten
DS 25: Symposium: Real Time Growth Studies III
DS 25.2: Vortrag
Donnerstag, 29. März 2007, 15:45–16:00, H32
Real-time and in-situ study of organic semiconductor growth: using X-ray growth oscillations beyond the anti-Bragg point — •Stefan Kowarik1,2, Alexander Gerlach1,2, Stefan Sellner1, Frank Schreiber1, Leide Cavalcanti3, and Oleg Konovalov3 — 1Institut für Angewandte Physik, Universität Tübingen, 72076 Tübingen, Germany — 2Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford OX1 3QZ, United Kingdom — 3ESRF, 6 Rue Jules Horowitz, Boîte Postale 220, 38043 Grenoble Cedex 9, France
In-situ and real-time X-ray scattering experiments during organic molecular beam deposition (OMBD) have been performed at the ESRF. Using an optimised setup and the high X-ray photon flux at a synchrotron, we show that a wide region in reciprocal space (i.e. many Fourier components of the real-space structure) can be monitored in real-time. In particular we manage to simultaneously acquire X-ray growth oscillations not only at the anti-Bragg condition but in a broad q-interval and in particular at the 2/3, 3/4, 4/5 etc. Bragg points. We will also discuss a simplified scheme for direct data analysis. The real-time measurements allow studying the growth kinetics of organic semiconductors such as pentacene, perfluoropentacene, and diindenoperylene in great detail. We find marked transitions from layer-by-layer growth to roughening, changes in molecular orientation during the growth process, as well as transient strain [1].
[1] S. Kowarik, et al. PRL 96, 125504 (2006).