Micropatterns of non-circular droplets of nanostructured Ps-B-Peo copolymer by solvent-assisted wetting on a chemically periodic surface

A method to fabricate micropatterns of non-circular droplets of a self-assembled block copolymer by solvent-assisted wetting on chemically periodic surface is presented. The block copolymer is dewetted on a topographic pre-pattern to form an array of microdroplets with a sphere-capped shape and circular contact line. The droplets are then transferred onto a chemically periodic Au line pattern microcontact-printed with two types of self-assembled monolayers (SAMs). Solvent vapor application provides sufficient mobility to the block copolymer molecules to induce spreading of the transferred droplets, resulting in two types of non-circular microdroplet growth. The growth behavior depends on the size of initial droplets relative to periodic line width and on the initial registries of as-transferred droplets.