Hierarchical Ordering of Block Copolymer Nanostructures by Solvent Annealing Combined with Controlled Dewetting

A hierarchical nanostructure of PS-b-PEO is demonstrated (see figure) with a novel approach by solvent vapor annealing of a micropatterned block copolymer thin film selectively spun cast on microcontact printed surface of SAMs. Dewetting of the thin film, inevitable during the ordering of block copolymer microdomains upon solvent annealing, is strictly confined to the patterned regions, leading to the controlled micropatttern with nearly perfect ordering of PEO microdomains.