Multiscale Simulation Approach on Sub-10 nm Extreme Ultraviolet Photoresist Patterning: Insights from Nanoscale Heterogeneity of Polymer

We developed a multiscale model that integrates density functional theory (DFT), molecular dynamics (MD), and the finite difference method (FDM) to reflect the heterogeneous spatial distribution of the material ingredients on sub-10 nm photoresist (PR) pattern fabrication using extreme ultraviolet lithography (EUVL). It allowed the exploration of phototriggered chemical reactions at the molecular level, including photoacid generator (PAG) dissociation, acid diffusion-coupled deprotection, and solubility switching of individual polymer chains. To quantify the progress of the deprotection, a protection ratio of each pendant group was tracked to distinguish the dissoluble PR chains from the developer as the process time elapsed. Deprotection was shown to preferentially occur in the pendant group adjacent to the acid molecule (