Wafer-Scale Unidirectional Alignment of Supramolecular Columns on Faceted Surfaces

ACS Nano. 2021 Jul 27;15(7):11762-11769. doi: 10.1021/acsnano.1c02632. Epub 2021 Jul 12.

Abstract

The long-range alignment of supramolecular structures must be engineered as a first step toward advanced nanopatterning processes aimed at miniaturizing features to dimensions below 5 nm. This study introduces a facile method of directing the orientation of supramolecular columns over wafer-scale areas using faceted surfaces. Supramolecular columns with features on the sub-5 nm scale were highly aligned in a direction orthogonal to that of the facet patterning on unidirectional and nanoscopic faceted surface patterns. This unidirectional alignment of supramolecular columns is also observed by varying the thickness of the supramolecular film or by altering the dimensions of the facet pattern. The ordering behavior of the supramolecular columns can be attributed to the triangular depth profile of the bottom facet pattern. Furthermore, this directed self-assembly principle allows for the continuous alignment of supramolecular structures across ultralarge distances on flexible patterned substrates.

Keywords: GISAXS; directed self-assembly; faceted surfaces; orthogonal alignment; supramolecules.