Detailed molecular dynamics studies of block copolymer directed self-assembly: Effect of guiding layer properties

Abstract

Detailed molecular dynamics simulations have been performed to explore the effect of guiding layer properties and errors on resulting directed self-assembly pattern properties produced in block copolymer (BCP) thin films. Guiding patterns that are noncommensurate to the natural BCP pitch are considered, as are guiding lines that have correlated or anticorrelated line edge deviations. The process window is detailed for noncommensurate line widths. Guiding lines with various correlated and anticorrelated roughnesses show that under the high χ conditions used here, very significant guiding roughness is required to have any effect on the BCP film, and most of the guiding roughness is damped out within 5 nm of the bottom surface of the BCP film. Also, pitch subdivision patterns (where the BCP natural periodicity is some integer multiple smaller than the guiding pattern periodicity) damp out guiding line roughness more easily than pitch replicating patterns where a guiding pattern exists for each line formed in the BCP film.