Block Copolymer Nanolithography: Translation of Molecular Level Control to Nanoscale Patterns

Abstract

The self-asembly of block copolymers is a promising platform for the "bottom-up" fabrication of nanostructured materials and devices. This review covers some of the advances made in this field from the laboratory setting to applications where block copolymers are in use.

A Path to Ultranarrow Patterns Using Self-Assembled Lithography

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Templated self-assembly of block copolymer thin films can generate periodic arrays of microdomains within a sparse template, or complex patterns using 1:1 templates [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] . However, arbitrary pattern generation directed by sparse templates remains elusive.

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“…Block copolymer thin film self-assembly on an unpatterned substrate leads to close-packed arrays of features such as lines or dots that lack long-range order, thus limiting their utility. As a result, both chemical and topographical substrate features have been used to template or guide block copolymer self-assembly, imposing long-range order and generating microdomain geometries not observed in untemplated films [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] . These templates are often defined using electronbeam lithography (EBL) [3][4][5]7,8,11 , because of its ability to pattern small features of arbitrary geometry.…”

“…Most work on the templated self-assembly of block copolymers for nanolithography has focused on the generation of periodic patterns of parallel lines, close-packed dots or concentric rings, using shallow trenches 1,6,9,10,[12][13][14]22,24,26 , sparse post arrays 3 or chemical templates with a periodicity either similar to that of the BCP 2,7,8,15 or a factor two, three or four times larger 3-5 . Nealey and colleagues have shown that non-regular features such as lamellae with bends 2,11 or square-packed dots 15 could be formed using a chemical pattern of the same density as the desired block copolymer pattern.…”

Synthesis and Solution Self‐Assembly of Polyisoprene‐block‐poly(ferrocenylmethylsilane): A Diblock Copolymer with an Atactic but Semicrystalline Core‐Forming Metalloblock

“…203,287,[298][299][300][301][302][303][304] BCPs with a metalloblock have garnered significant attention with respect to the formation of nanotemplates. One of the earliest examples involves the formation of arrays of tungstencapped cobalt nanodots using a PS-b-PFEMS diblock copolymer thin film, which is outlined in the schematic in Figure 27.…”

The correlation between solvent treatment and the microstructure of PAN-b-PEG copolymer membranes

“…The enhanced polymer mobility caused by the solvent swelling can lead to a high degree of ordering in the film. 24 However, the ordering degree of the morphologies should be primarily determined by the species of the solvents and other annealing treatment conditions. Toluene and thiophene are selective solvents for PEG blocks.…”