Self-assembling block copolymers provide a simple, efficient, and rapid way to generate nanoscale patterns over macroscopic areas:Â’ for example, an array of 20 nm dots covering a 100 mm silicon wafer.Â’ These dots can be "lined up" by applying shear to the block copolymer film [1], but the order is not perfect:Â’ dislocations (lines of dots that abruptly start or end) remain in the film.Â’