Berlin 2005 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
CPP: Chemische Physik und Polymerphysik
CPP 10: Light induced phenomena I
CPP 10.3: Vortrag
Montag, 7. März 2005, 10:15–10:30, TU C230
Molecular Orientation Effects During the Formation of Surface Relief Gratings — •Oliver Henneberg1, Bernd Winter2, Ullrich Pietsch1, Marina Saphiannikova2, and Thomas Geue3 — 1Universität Potsdam, Institute of Physics, Potsdam, Germany — 2Max-Born-Institute, Berlin, Germany — 3Paul Scherrer Institut, Villingen, Switzerland
The absorption of visible light in a photopolymer can cause movement of polymer units on macroscopic length scale. Preparing an interference pattern with actinic light on the surface of an homogeneous photo-polymer film this molecular movement can results in a surface relief grating with height amplitudes of several 100nm. In case of polymers containing azobenzene units the molecular origin is a cycling E/Z-isomerization of azobenzenes. However, several aspects of this molecular movement are less understood, e.g. the bulk Young modulus of the polymer is to high in order to allow a movement of molecules. Different models were developed to explain the macroscopic material transport. Here we performed photoelectron spectroscopy measurements to get information of the molecular orientation at the surface of the grating [1]. Spacial resolved FTIR measurements showed a periodic change of the orientation. With PES we could observe a strong orientation.
[1] O. Henneberg, et al., APL 84 (2004) 1561