Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

O: Oberflächenphysik

O 11: Poster (I)

O 11.16: Poster

Montag, 22. März 1999, 19:30–22:30, Aula

Organic Heterostructures: Molecular Orientation and Interface Properties — •Ying Zou, Detlef Gador, Christian Buchberger, Rainer Rink, and Eberhard Umbach — Experimentelle Physik II, Universit"at W"urzburg, 97074 W"urzburg

Organic heterostructures have a promising potential for the development of electronic devices (FETs,OLEDs, etc.). Film morphology, molecular order, and the interaction between the different molecules at the interfaces play a significant role for its performance. Based on previous experiments with PTCDA and DCNQI films deposited on various single crystal substrates by sublimation under UHV conditions, heterostructures of these constituents of various thicknesses have been prepared. Near-edge x-ray absorption fine structure (NEXAFS), photoemission, low-energy electron diffraction and thermal desorption spectroscopy (TDS) have been utilized to investigate the molecular orientation, electronic and geometric structure and the molecular interaction at the organic heterointerface. E.g., for DCNQI overlayers on PTCDA, a small tilt angle is concluded from the linear dichroism in the N K-edge spectra. The NEXAFS resonances display a very weak intermolecular interaction at the interface, which is in agreement with photoemission and TDS data (supported by BMBF, projects 05 625WWA 9 and 05 SF8 WWA 7).