Synthesis and Directed Self-Assembly of Modified PS-b-PMMA for Sub-10 nm Nanolithography

The directed self-assembly (DSA) of block copolymers has attracted a great deal of interest due to its potential applications in sub-10 nm lithography. The conventional organic organic DSA materials such as poly[styrene-block-(methyl methacrylate)] (PS-b-PMMA) have been extensively studied, however, the low etch contrast between two blocks and the difficulty to reduce L-0 (ca. 28 nm) limit its application. In this study, we designed and synthesized the novel DSA materials based on PS-b-PMMA. Through the modifying of acrylics part, segment segment interaction parameter (chi) can be significantly increased, which leads to rapid self-assembly and high etch contrast. These block copolymers show the potential as DSA material with high intrinsic resolution for sub-10 nm and beyond nodes.