| Abstract
| - The effects of block copolymer adhesion promoters on the dewetting of polystyrene, PS,homopolymer films with degree of polymerization, P, ∼300 are investigated using optical microscopyand atomic force microscopy. The copolymers are poly(deuterated styrene-block-methyl methacrylate),dPS-b-PMMA, having a short anchoring block that is attracted to the substrate and a long nonadsorbingblock with a varying degree of polymerization, NNA. Relative to a homopolymer film on silicon oxide,SiOx, hole growth slows down, and holes stop growing at a diameter of about 100 μm when 1 vol % blockcopolymer having NNA< P is added. The hole floor is found to exhibit a roughness of 1.5 nm and a uniformarray of irregularly shaped (NNA ∼ 2P/3) and rounder (NNA ∼ P/3) mounds of polymer. In contrast to thispartial dewetting, dewetting is entirely suppressed for NNA> P. Moreover, as the substrate is changedfrom SiOx to a more hydrophobic and less wettable amino-terminated surface, we observe an improvementin thin film stabilization, and no dewetting is detected. The slowing down of hole growth on SiOx (NNA<P) and the growth suppression on SiOx (NNA> P) and on amine-terminated surface are attributed to thereduction of the interfacial tension between the bulk and the adsorbed chains as the interfacial widthbetween the adsorbed block copolymer and matrix chains increases.
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