Sub-10 nm Resistless Nanolithography for Directed Self-Assembly of Block Copolymers

Abstract

The creation of highly efficient guiding patterns for the directed self-assembly of block copolymers by resistless nanolithography using atomic force microscopy (AFM) is demonstrated. It is shown that chemical patterns consisting of arrays of lines defined on a brush layer by AFM allow the alignment of the blocks of lamella-forming polymers. The main advantage of this method relies on the capability to create high-resolution (sub-10 nm line-width) guiding patterns and the reduction of the number of process steps compared to the state-of-the-art methods for creating guiding patterns by chemical surface modification. It is found that the guiding patterns induce the block alignment very efficiently, allowing the achievement of a density multiplication factor of 7 for block copolymers of 14 nm half-pitch, which is attributed to the combined effect of topographical and chemical modification.

Ligand switch in photoinduced copper-mediated polymerization: synthesis of methacrylate–acrylate block copolymers

“…26,27 Continuous efforts have been devoted to explore the versatility of this photo-induced technique over acrylate monomers, including solketal acrylate, hydroxyethyl acrylate and glycidyl acrylate homopolymer, or even poly(methyl acrylate)-b-poly(solketal acrylate). 40,41 Many of these applications require polymers to self-assemble into specific conformations. 29,30 Followed by hydrolysis of the tert-butyl group to the hydroxyl group the resulting decablock copolymer has shown a complex thermo and pH-responsive self-assembled behavior.…”

Nanomechanical properties of solvent cast polystyrene and poly(methyl methacrylate) polymer blends and self-assembled block copolymers

“…3 Based on their high throughput and relatively simple processing, DSA-BCP thin films are likely to be adopted by the microelectronics industry within a few years. BCPs are macromolecules that are formed by two (or more) distinct polymer chains (blocks) joined by interblock covalent bonds.…”

Recent Achievements in Sub-10 nm DSA Lithography for Line/Space Patterning

“…We have explored to ways of using SPL to create chemical guiding patterns: (i) inducing the local oxidation of PS-OH brush layers under the application of a voltage (Fig. 10 b) [19]; and (ii), by thermal-SPL [20], where the AFM tip is heated to locally evaporate a thin resist. The two key steps of this second process are the accurate patterning of a poly(phthalaldehyde) resist layer of only 3.5 nm thickness, and the subsequent oxygen-plasma functionalization of the underlying PS brush layer.…”