Beyond Linear Polymers: The Role of Bottlebrush Structures in Refining Nanoscale Patterns

Bottlebrush polymers, characterized by densely grafted side chains attached onto a linear backbone chain, exhibit intriguing physical and chemical properties. These characteristics arise from their unique chain architecture and the consequential steric hindrance introduced by the closely packed side chains. In this study, we exploit these distinctive characteristics of bottlebrush polymers for potential use in nanoscale patterning materials. Our study employs a coarse-grained bottlebrush model that accounts for changes in backbone flexibility induced by interactions with grafted side chains. We demonstrate the advantage of using Janus-type bottlebrushes with immiscible A and B homopolymer side chains, in the formation of self-assembled nanostructures. Notably, these structures have reduced pattern roughness when compared to their linear polymer counterparts, as the rigid backbone fosters well-aligned microdomains. Furthermore, we evaluate the potential of bottlebrush polymers in chain scission photoresists, providing detailed insights at the molecular level.