Patent ID: 8114306

Claim:
A method, comprising: providing a substrate with discrete openings whose targeted critical dimension (CD) is less than 200 nm, the openings having a statistical variation in their CD characterized by a standard deviation σ openings and an average CD openings , with 3σ openings being at least 10% of the average CD openings ; applying, over the substrate, a layer of polymer that includes a block copolymer, wherein components of the copolymer are immiscible with one another; allowing the polymer to form, inside each of the openings, a self-assembled central domain within a surrounding self-assembled domain; and selectively removing the central domains, thereby forming a hole where each central domain was located, the holes having a CD statistical variation characterized by a standard deviation σ holes and an average CD holes ; wherein σ holes /average CD holes is less than 0.8 of σ openings /average CD openings .