Fast self-assembly of polystyrene-b-poly(fluoro methacrylate) into sub-5 nm microdomains for nanopatterning applications

Abstract

The block copolymer (BCP) approach is a promising route for sub-10 nm semiconductor lithography. In this paper, a series of polystyrene-block-poly(pentadecafluorooctyl methacrylate) (PS-b-PPDFMA) copolymers are designed and synthesized by living anionic polymerization. The BCP phase behavior is investigated using small-angle X-ray scattering and transmission electron microscopy. The resulting BCP materials form sub-5 nm features after 1 min of thermal annealing at 80 °C. The Flory–Huggins interaction parameter of PS-b-PPDFMA is very large (0.353 at 150 °C) because of the significant incompatibility between polystyrene and the perfluoroalkyl block. These results qualify PS-b-PPDFMA as a potential material for sub-5 nm patterning applications.