Authors
|
Wunnicke, O. ; Müller-Buschbaum, P. ; Wolkenhauer, M. ; Lorenz-Haas, C. ; Cubitt, R. ; Leiner, V. ; Stamm, M.
|
Title
|
Stabilization of Thin Polymeric Bilayer Films on Top of Semiconductor Surfaces
|
Date
|
07.10.2003
|
Number
|
11696
|
Abstract
|
The enhanced thermal stability of thin polymer bilayer films against dewetting is investigated.Stabilization results from the addition of a random functional copolymer. The model system consists ofa silicon substrate covered with a bilayer of amorphous polyamide (PA), followed by a fully deuteratedpolystyrene (PSd). While the PA sublayer is stable against dewetting, the addition of a PSd homopolymerfilm allows dewetting to occur during annealing. By blending the PSd top layer with a fully protonatedcopolymer poly(styrene-<I>co</I>-maleic anhydride) (SMA2), containing 2% maleic anhydride groups in the chain,its dewetting process is retarded. This increase in stability is investigated as a function of copolymer andannealing time. Scanning force microscopy (SFM) is applied to determine the surface root-mean-squareroughness and to check the stabilization effect. Information about the density profile is aquired fromspecular neutron reflectivity measurements. In addition, grazing incidence small angle neutron scattering(GISANS) is applied. GISANS utilizes the averaging capabilities of scattering methods, which is comparedto local information obtained by SFM. Furthermore, GISANS enables the detection of buried struc<br />turesin contrast to the SFM. An amount of 5% by volume SMA2 is sufficient to stabilize the bilayer film dueto the creation of an enrichment layer of SMA2 at the PA:PSd interface. With creation of a brushlikeinterface, the mobility of the PSd molecules is decreased, which suppresses dewetting.
|
Publisher
|
Langmuir
|
Wikidata
|
|
Citation
|
Langmuir 19 (2003) 8511-8520
|
DOI
|
https://doi.org/10.1021/la0344837
|
Tags
|
x-ray-scattering phase-separation liquid-films blend films reactive compatibilization spinodal decomposition neutron-scattering copolymer rupture interfaces
|