TY  - JOUR
A1  - Kowarik, Stefan
A1  - Gerlach, Andreas
A1  - Leitenberger, Wolfram
A1  - Hu J, Witte
A1  - Wöll, Christoph
A1  - Schreiber, Frank
T1  - Energy-dispersive X-ray reflectivity and GID for real-time growth studies of pentacene thin films
N2  - We use energy-dispersive X-ray reflectivity and grazing incidence diffraction (GID) to follow the growth of the crystalline organic semiconductor pentacene on silicon oxide in-situ and in real-time. The technique allows for monitoring Bragg reflections and measuring X-ray growth oscillations with a time resolution of 1 min in a wide q-range in reciprocal space extending over 0.25-0.80 angstrom(-1), i.e. sampling a large number of Fourier components simultaneously. A quantitative analysis of growth oscillations at several q-points yields the evolution of the surface roughness, showing a marked transition from layer-by-layer growth to strong roughening after four monolayers of pentacene have been deposited. (c) 2006 Elsevier B.V. All rights reserved.
Y1  - 2007
UR  - http://www.sciencedirect.com/science/journal/00406090
U6  - https://doi.org/10.1016/j.tsf.2006.12.020
SN  - 0040-6090
ER  - 
TY  - JOUR
A1  - Giebler, Rainer
A1  - Schulz, Burkhard
A1  - Reiche, Jürgen
A1  - Brehmer, Ludwig
A1  - Wühn, Mario
A1  - Wöll, Christoph
A1  - Smith, Andrew Phillip
A1  - Urquhart, Steven G.
A1  - Ade, Harald W.
A1  - Unger, Wolfgang E. S.
T1  - Near-edge x-ray absorption fine structure spectroscopy on ordered films of an amphiphilic derivate of 2,5- Diphenyl-1,3,4-oxadiazole
N2  - The surfaces of ordered films formed from an amphiphilic derivative of 2,5-diphenyl-1,3,4-oxadiazole by the Langmuir-Blodgett (LB) technique and organic molecular beam deposition (OMBD) were investigated by the use of near-edge X-ray absorption fine structure (NEXAFS) spectroscopy. For the assignment of the spectral features of the C, N, and O K- edge absorption spectra, fingerprint spectra of poly(p-phenylene terephthalamide)(Kevlar), poly(ethylene terephthalate), poly(p-phenylene-1,3,4-oxadiazole), and 2,5-di- (pentadecyl)-1,3,4-oxadiazole, which contain related chemical moieties, were recorded. Ab initio molecular orbital calculations, performed with explicit treatment of the core hole, are used to support the spectral interpretations. Angle-resolved NEXAFS spectroscopy at the C, N, and O K-edges suggests a preferentially upright orientation of the oxadiazole derivative in the outermost layer of the films. X-ray specular reflectivity data and molecular modeling results suggest a similar interpretation.
Y1  - 1999
ER  -