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Nanostrukturen und Grenzflächen Poster: Do., 13:00–15:30 D-P307
Combinatorial studies on metal / polymer gradient nanocomposites
Stephan V. Roth 1 , Harald Walter 2 , Ralf Domnick 3 , Olaf Leupold 1 , Christian
Schroer 4 , Marion Kuhlmann 1 , Bruno Lengeler 5 , Rainer Gehrke 1 , Peter
Müller-Buschbaum 6
1 HASYLAB at DESY, Notkestr. 85, D-22603 Hamburg, Germany – 2 CSEM SA,
Badenerstrasse 569, CH-8048 Zürich, Switzerland – 3 identif GmbH, Ulrich-Schalk-Str.
3, D-91056 Erlangen, Germany – 4 Inst. f. Strukturphysik, TU Dresdesn, D-01062
Dresden, Germany – 5 II. Physik. Inst., Physikzentrum Melaten, RWTH Aachen, D-
52074 Aachen, Germany – 6 Physik-Department E13, TU München, James-Franck-Str.
1, D- 85748 Garching, Germany
Nanostructuring of thin noble metal films is of utmost importance for many technological
and biophysical areas, e.g. anti-counterfeiting and DNA scanning [1]. Usually
a multilayer geometry is chosen consisting of noble metal layer / polymer / substrate.
The optical properties of such multilayer systems depend crucially on the structure
and morphology of the noble metal layer. They are determined by key parameters
like deposition method or metal-polymer interaction affecting the self-assembly of the
metal atoms. We advanced two-fold: Firstly, as polymer layer we chose a blend of
deuterated polystyrene (dPS) and polyisoprene (PI) being already phase separated in
thin film geometry. As metals, we chose Au and Cu which have different sticking coefficients
on the two components of this blend. Secondly we installed a one-dimensional
(1D) gradient in mass thickness of the noble metal layer during evaporation to allow
for a combinatorial investigation of the nanostructure of the metal layer as a function
of mass thickness.
Microbeam grazing incidence small-angle x-ray scattering (µ GISAXS) is excellently
suited for combinatorial investigations with high statistical significance [2,3]. The experiments
were conducted at the beamline BW4 of HASYLAB using the novel µ focus
option of BW4. A moderate micro-focus beam size of 32x17 µm 2 (HxV) can be installed
making use of Beryllium compound refractive lenses (Be CRLs). For the experiments
a step size adapted to the microbeam size was used (∆y=40 µm). Along the gradient,
the Cu mass thickness clearly changes. We present the results on two gradients,
namely Au and Cu on dPS/PI-blend, and explain the results in terms of replication of
the polymer blend nano-structure as a function of mass thickness.
[1] G. Bauer, et al., Nanotechnology 14, (2003) 1289
[2] S.V. Roth et al., Appl. Phys. Lett. 82, (2003) 1935
[3] S.V. Roth et al., Appl. Phys. Lett. 88, (2006) 021910