Hyper-NA EUV Patterning through Morphology-Controlled High-Endurance Metal Containing Block Copolymers

As scaling progresses towards high-NA and future hyper-NA EUV lithography, mitigating stochastic defects and increased line-edge/width roughness (LER/LWR) in thin, low-aspect-ratio patterns has become a critical challenge. While directed self-assembly (DSA) is highly considered for pattern rectification, conventional DSA materials are unsuitable for providing the sufficient thermodynamic driving force required for sub-10 nm half-pitch resolution. To address this limitation, a series of high-endurance metal-containing block copolymers (BCPs) was designed and synthesized for advanced EUV pattern rectification. Various combinations of counter blocks and metal-containing blocks with enhanced durability were systematically synthesized to evaluate the influence of metal incorporation on polymer thermodynamics. 
By extracting the Flory-Huggins interaction parameter (χ) and analyzing the phase behavior, this study aims to establish quantitative structure-property relationships. Systematic screening is employed to identify BCPs compositions capable of achieving ultra-fine microphase separation while maximizing etch resistance through oxidation-induced reinforcement. Ultimately, the optimized high-endurance metal-containing BCPs will be applied onto actual EUV pre-patterns. This research expects to demonstrate effective pattern rectification, targeting significant improvements in aspect-ratio and dimensional uniformity to offer a robust material platform for next-generation lithographic processes.