Polarity-switching top coats enable orientation of sub-10-nm block copolymer domains.

摘要: Block copolymers (BCPs) must necessarily have high interaction parameters (χ), a fundamental measure of block incompatibility, to self-assemble into sub-10-nanometer features. Unfortunately, χ often results from blocks that disparate interfacial energies, which makes the formation useful thin-film domain orientations challenging. To mitigate forces, polymers composed maleic anhydride and two other components been designed as top coats can be spin-coated basic aqueous solution in ring-opened, acid salt form. When baked, reforms switches polarity create neutral layer enabling BCP feature alignment not possible by thermal annealing alone. Top were applied lamella-forming poly(styrene-block-trimethylsilylstyrene-block-styrene) poly(trimethylsilylstyrene-block-lactide), thermally annealed produce perpendicular features with linewidths 15 9 nanometers, respectively.