• block copolymers;
  • directed assembly;
  • density multiplication;
  • device-oriented structures


Non-regular, device-oriented structures can be directed to assemble on chemically nanopatterned surfaces such that the density of features in the assembled pattern is multiplied by a factor of two or more compared to the chemical pattern. By blending the block copolymers with homopolymers and designing the chemical pattern rationally, complicated structures such as bends, jogs, junctions, terminations, and combined structures are fabricated. Previously, directed assembly of block copolymers has been shown to enhance the resolution of lithographic processes for hexagonal arrays of spots and parallel lines, corresponding to the bulk morphologies of block copolymer systems, but this is the first demonstration of enhanced resolution for more complicated, device-oriented features. This fundamental knowledge broadens the range of technologies that can be served by the directed assembly of block copolymers.