Aligned nanowires and nanodots by directed block copolymer assembly

Abstract

The directed self-assembly of block copolymers (BCPs) is a promising route to generatehighly ordered arrays of sub-10 nm features. Ultradense arrays of a monolayer of sphericalmicrodomains or cylindrical microdomains oriented parallel to the surface have beenproduced where the lateral ordering is guided by surface patterning and the lattice definedby the patterning can be commensurate or incommensurate with the natural period of theBCP. Commensurability between the two can be used to elegantly manipulate the lateralordering and orientation of the BCP microdomains so as to form well-aligned arrays of 1Dnanowires or 2D addressable nanodots. No modification of the substrate surface, asidefrom the patterning, was used, making the influence of lattice mismatch andpattern amplification on the size, shape and pitch of the BCP microdomains moretransparent. A skew angle between incommensurate lattices, defining a stretching orcompression of the BCP chains to compensate for the lattice mismatch, is presented.