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arXiv · 1608.05785

Defect-free Perpendicular Diblock Copolymer Films: The Synergistic Effect of Surface Topography and Chemistry

Xingkun Man·Pan Zhou·Jiuzhou Tang·Dadong Yan·David Andelman
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Abstract

We propose a direct self-assembly mechanism towards obtaining defect-free perpendicular lamellar phases of diblock copolymer (BCP) thin films. In our numerical study, a thin BCP film having a flat top surface is casted on a uni-directional corrugated solid substrate. The substrate is treated chemically and has a weak preference toward one of the two BCP components. Employing self-consistent field theory (SCFT), we find that there is an enhanced synergy between two substrate characteristics: its topography (geometrical roughness) combined with a weak surface preference. This synergy produces the desired perpendicular lamellar phase with perfect inplane ordering. Defect-free BCP lamellar phases are reproducible for several random initial states, and are obtained for a range of substrate roughness and chemical characteristics, even for a uni-directional multi-mode substrate roughness. Our theoretical study suggests possible experiments that will explore the interplay between uni-directional substrate corrugation and chemical surface treatment. It may lead to viable and economical ways of obtaining BCP films with defect-free lateral alignment.

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Xingkun Man, Pan Zhou, Jiuzhou Tang, Dadong Yan, David Andelman. 2016-08-20. Defect-free Perpendicular Diblock Copolymer Films: The Synergistic Effect of Surface Topography and Chemistry. https://doi.org/10.1021/acs.macromol.6b01814

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