SELF-ALIGNED PATTERNING USING DIRECTED SELF-ASSEMBLY OF BLOCK COPOLYMERS

摘要

The techniques herein provide a self-aligned etching method that uses existing features to pattern or fit a pattern without damaging the existing features. Existing substrate structures are used to create surfaces that enable direct self-assembly (DSA) of block copolymers (BCPs) without a separate lithographic patterning layer. The methods herein include recessing at least one pre-existing material or structure on a substrate and adding a film remaining only in the recessed material. This film can be selected to have a preferential surface energy that can enable controlled self-assembly of the block copolymer. The substrate can then be etched using both the existing structure and one polymer material as an etch mask. One exemplary advantage is that a self-assembled polymeric material can be placed to protect the exposed corners of existing features, which reduces the burden of selective etch chemistry, increases the precision of subsequent etches, and provides sputter yield. reduces the