Key Challenges and Opportunities for Advanced Extreme Ultraviolet Lithography Photoresist Materials
Mingqi Li, Emad Aqad
Abstract
Abstract Semiconducting device manufacturing relies on constant advancements in photolithography. The continued demand for shrinking feature sizes necessitates advanced lithographic solutions to address the challenges associated with printing very small features that meet stringent lithographic performance specifications, including sensitivity, roughness, and the ability to achieve defect and device yield requirements. An ongoing challenge is the development of photoresist materials that enable high numerical aperture (NA) extreme ultraviolet lithography (EUVL) for the next generation semiconductor manufacturing. Key to next‐generation material design is the ability to mitigate the resist stochasticity caused by the EUV‐specific photon shot noise issue and the random distribution of resist components in the resist thin film, as well as to ensure macromolecular and thin film homogeneity to address resist blur, including photoacid diffusion and electron scattering. To tackle the ultimate resist variability challenge, multiple technical approaches are being explored, including the development of next‐generation photoacid‐induced chemically amplified resists, resists based on photoinduced polymer chain scission, molecular glass resists, and metal oxide resists. In this review, recent advances in resist development for next‐generation high NA EUVL applications are presented. The need for improvements in material design, formulation, and optimization to support the semiconductor industry's patterning roadmap will also be discussed.