Enhanced Lithography Performance with Imino/Imido Benzenesulfonate Photoacid Generator‐Bound Polymer Resists

• DOI: 10.1002/smll.202412297
• Publication Date: 2025-03-11T15:38:06Z
• Authors: Yue Liu; Dong Wang; Haihua Wang; Huan Chen; Qianqian Wang; Wenbing Kang

AbstractThe inherent acid diffusion during post‐exposure baking poses significant challenges in balancing resolution, line‐edge roughness, and sensitivity (RLS), thereby constraining the performance of chemically amplified photoresists (CARs) in advanced lithography. This study introduces a novel series of alkene‐functionalized imino/imido benzenesulfonate photoacid generators (PAGs), characterized by their solubility, thermal stability, and polymerization attributes. These derivatives can copolymerize with acrylates and methacrylates to form PAG‐bound copolymers, integrating non‐ionic PAG units and acid‐cleavable bulky alicyclic substituents, facilitating their use as “single‐component” resists devoid of additives. Upon exposure to electron beams or ultraviolet radiation, the sulfonamide esters undergo N─O bond scission, producing photoacids that catalyze the deprotection of acidolytic groups. Compared to PAG‐blended systems, these PAG‐bound systems curtail acid diffusion by generating long‐chain sulfonic acids, while preserving high sensitivity. The formulated single‐component CARs demonstrate superior resolution and roughness, achieving a minimum linewidth of 42 nm at an electron beam dose of 73 µC cm−2. This research provides a rational design for polymerizable imino/imido benzenesulfonate PAGs and single‐component CARs, offering a viable solution to the RLS problem.