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SEMINARIOS 2010
Gerencia Investigacion y Aplicaciones
"Modelling structure formation in diblock copolymer
materials on patterned surfaces"
Prof. Dr. Marcus Müller (*)
Institut für Theoretische Physik - Georg-August Universität
- Göttingen
(presentacion en ingles)
Diblock copolymers self-assemble into a variety of periodic
nano-structures in the bulk. The length scale is dictated by
the molecular extension and ranges from 10 nm to 100nm. The
application of copolymer materials have attracted abiding
interest for templating nano-structures in microelectronics
and catalysis. If the copolymer material is in contact
with a patterned surface, the morphology of the diblock
copolymer may either replicate the surface pattern without
defects over large areas or a more complex reconstruction of
the soft morphology at the patterned surface occurs
depending on the mismatch between the symmetry and length
scale of surface pattern and bulk morphology. Certain
irregular patterns that do not have an analogue in the bulk
phase diagram, can be replicated by the adding "defectants"
to the copolymer material. These are substances;e.g.,
homopolymers or nanoparticles; enrich at locations, where
the substrate pattern deviates from the bulk morphology, and
thereby reduce the excess free-energy of these local
structures, permitting defect-free replication.
Using computer simulation of soft, coarse-grained polymer
models, we investigate the directed assembly of copolymer
materials on various surface patterns. The model allows us
to investigate large, three-dimensional systems with an
experimentally relevant degree of polymerization by computer
simulations. Special methods for computing free-energy
differences of self-assembled morphologies and
grain-boundaries will be discussed and applied to block
copolymers in thin films. The computer simulation provides a
wealth of information about the three-dimensional structure,
its free energy, and also about the kinetics of structure
formation.
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(*) Ph.D. (1995) and Habilitation (1999) in
theoretical physics from the Johannes Gutenberg-Universität
in Mainz, Germany. He researched at the University of
Washington, at the University of Mainz, at the Edinburgh
Parallel Computing Centre, at the Instituto de
Investigaciones Fisicoquimicas Teoricas y Aplicadas of La
Plata, at the Institute of Solid State Research of Jülich,
at the University of California and at the Comision Nacional
de Energia Atomica. He was guest professor at the
Universidad Nacional de General San Martin, assistant
professor at the University of Mainz, and associate
professor at the University of Wisconsin-Madison. He is
presently university professor at the Institute for
Theoretical Physcis at the Georg-August University of
Göttingen. He was awarded with the Feodor Lynen fellowship
from the Alexander von Humbodt Foundation, with the
Sponsorship for the Research of the University of Mainz,
with the Heisenberg fellowship of the German Science
Foundation, with a Lichtenberg professorship from the
Volkswagen Foundation and with the ^OJohn H. Dillon
Medal of the American Physical Society.
Viernes 6 de Agosto - 11:00 hs - Sala del nivel 63,
TANDAR
Aula de Nivel 63 - TANDAR
CNEA - Centro Atomico Constituyentes
Av. Gral. Paz 1499 (y Constituyentes)
6772-7065 / 7007 / 7072 / 7081
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