A simulation study for defects in sub-15 nm line-space using directed self-assembly

A specific type of buried defect in lamellar phase diblock copolymer was studied by experiments and simulations using self-consistent field theory (SCFT). The defects had 3-dimensional structures and created hexagonally arranged holes. They existed not only on the substrate with the guide structures but in fingerprints. The simulation results suggested that one of the causes of the defects is mismatch of the surface affinity of the neutral layer.