Orientation control of silicon containing block-co-polymer with resolution beyond 10nm

Directed Self-Assembly (DSA) process is one of the attractive processes for creating the very fine pitch pattern. In this technology, block-co-polymer is the key material to achieve a fine patterning. Many reports are published with Polystyrene-b-Polymethylmethacrylate (PS-b-PMMA) for DSA applications. But it is difficult to achieve the resolution below 10 nm with PS-b-PMMA because of its low chi value. Etching transfer of PS-b-PMMA is also the key issue due to the low etching selectivity between PS and PMMA during dry etching process. In this report, block-co-polymers that include a Si-containing monomer and an organic monomer were synthesized by living anionic polymerization to supply a high resolution and a high etching contrast. These polymers with a low polydispersity demonstrated lamella morphology that can be oriented by thermal annealing with a neutral surface treatment. The effects of underlayer and top-coat materials were investigated to control the block-co-polymer orientation. These block-co-polymers also achieve a high dry etching contrast.