FuSe2 Topic 3: Louisiana Synchrotron-sourced UV for Advanced Resist Materials and Mechanisms

With the support of the Future of Semiconductors (FuSe) Program, Professors Anthony Engler, Phillip Sprunger, Revati Kumar, and Christopher Marvel of Louisiana State University (LSU) will design, synthesize, and investigate new polymeric materials and processes for high-resolution patterning in semiconductor manufacturing. New research infrastructure will be installed at the LSU Center for Advanced Microstructures and Devices (CAMD) synchrotron that will enable industrial and academic researchers in the Southern U.S. to access high energy photons used in state-of-the-art manufacturing systems. Optical patterning, or photolithography, is the most critical technological bottleneck in the fabrication of computer chips. Recently the semiconductor industry started to utilize Extreme Ultraviolet photons (EUV, 13.5 nanometer wavelength) to generate smaller, critical features that make chips faster and more powerful. This project will develop new classes of EUV-sensitive polymers, investigate their fundamental interactions with photons and electrons, and co-design the materials with metrology and pattern transfer processes. The broader impacts of this award include educational components to college students, outreach to K-12 students and the local community, and workforce development to train future technicians, engineers, and researchers to support the U.S. semiconductor industry and its supply chain. This award will help launch a Semiconductor Fabrication Workshop that will teach the semiconductor manufacturing process and provide hands-on training in cleanrooms to students from colleges within Louisiana that lack access to such facilities and course opportunities. This project is focused on the design and synthesis of new polymers that can serve as dry-developed, chain scission resists for EUV lithography and the construction of an EUV exposure module at the LSU CAMD synchrotron. Chain scission resists (CSRs) have the potential to improve line edge roughness and resolution limit due to a lack of photoactive small molecules that can diffuse to reduce patterning fidelity. However, CSRs typically suffer from low EUV sensitivity. Therefore, this research will design new classes of polyaldehydes that are inherently sensitive toward EUV photons, or the secondary electrons produced during exposure, and harness their relatively low thermodynamic ceiling temperature to achieve chemical amplification via depolymerization during the post-exposure bake. The latent image will be developed by vaporization of the resulting small molecules without liquid solutions that can also contribute to pattern failure. These materials will be co-designed with critical, downstream processes of photoresists, including metrology and pattern transfer needed to reliably fabricate advanced devices. The research will utilize custom operando EUV experiments, state-of-the-art electron microscopy, and molecular dynamics simulations to provide fundamental insights into polymer interactions and mechanisms during EUV exposure and development. This polyaldehyde platform will enable next-generation semiconductor fabrication processes with their low energy transformation from solid to vapor. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.