Engineering block copolymer materials for patterning ultra-low dimensions

The landscape of block copolymer (BCP) lithographic patterning has evolved significantly from the early days of the first generation BCP material, poly(styrene)-block-poly(methyl methacrylate) (PS-b-PMMA). The low Flory–Huggins interaction parameter (χ) of the workhorse material PS-b-PMMA prevents ultra-low dimensional scaling (<20 nm), which is the lifeblood of the semiconductor industry. In recent years, this bottleneck has been circumvented through the precise engineering of novel BCPs possessing either high χ and low polymerization degree (N) values or complex macromolecular architectures. We provide a synopsis of recently engineered BCP materials, examining the synthetic routes employed and thin film processing used for nanolithography. Fruitful results emanating from silicon and fluorine containing BCPs are emphasized as they provide a promising platform for sub-10 nm scaling. We subsequently examine routes to continue the relentless scaling for logic technologies with a focus on the potential integration of “advanced” BCP architectures in nanomanufacturing.