Local defectivity control of 2D self-assembled block copolymer patterns

A method for controlling the local defectivity of self-assembled polymer patterns through appropriate substrate design was detailed. The method of surface engineering to control defect location provided a way to impose local pattern perfection on thermodynamic self-assembling systems with high energy barriers for defect annihilation. Method for forming defect-free local areas in symmetric PS-b-PMMA thin film striped patterns involves engineering surface geometries with appropriate surface and intercenter facial tensions, defining confined volumes commensurate to intrinsic polymer dimensions for free-energy minimization and promoting polymer shear flow along preferred directions. The technique optimized the polymer interfacial interactions, commensurability effects, and polymer shear flow in forming aligned defect-free lamellar striped patterns with a two dimensional (2D) density profile suitable for lithographic applications.