First-Principles Study of Metal and Ligand Substitution Effects on EUV Absorption and Electron Energy Loss Secondary electrons play a vital role in extreme ultraviolet lithography (EUV-L), as low-3 energy electrons (LEEs) induce the solubility switch of the photoresist via electron-induced 4 reactions. However, optimizing EUV absorption at 92 eV and addressing the relatively long 5 inelastic mean free path (IMFP) of LEEs, which can lead to pattern blurring, remain critical 6 challenges.