面向亚 5 nm 图案化含硅嵌段共聚物的合成与自组装

Ever-shrinking pattern features present challenges for the semiconductor industry. Directed self-assembly (DSA) of block copolymers (BCP) has been demonstrated as one high throughput and low cost manufacturing candidate for the next-generation of nanolithography. The thermodynamically immiscible polymer blocks self-assemble into the ordered nanostructures with varied morphologies, and the feature size is dependent on the Flory-Huggins interaction parameter (χ) and the molecular weight (N) of BCP according to the self-consistent mean field theory. Design, synthesis, and self-assembly of novel high χ low N BCP is the long-term target for the community of polymer chemistry and materials science with the aim to achieve small size microphase separation domains. This review focuses on self-assembly of silicon-containing block copolymers for sub 5 nm nanolithography. Silicon-containing block copolymers not only exhibit high χ but also improve etch contrast property, which are considered as the promising materials for nanolithography. After a brief introduction of DSA, the main body is divided into three sections according to the chemical structures, including poly(dimethylsioxane)-based BCP, poly (silicon containing styrene)-based BCP, and poly(hedraloligomeric silsesquioxane)-based BCP. Each section covers self-assembly of bulk polymer and/or thin film, from historic initial study (>5 nm) to the recent progress (<5 nm). Synthesis, characterizations, χ, assembly conditions, feature sizes are discussed in detail. Finally, the challenges and opportunities are proposed. We hope this review would provide insights into polymer science and nanolithography technology.