Single-Component High-Resolution Dual-Tone EUV Photoresists Based on Precision Self-Immolative Polymers

Electron beam (EB) and extreme ultraviolet (EUV) lithography are advanced techniques capable of achieving sub-10 nm resolutions, critical for fabricating next-generation nanostructures and semiconductor devices. However, developing EUV photoresists that meet all demands for resolution, line edge roughness (LER), and sensitivity (RLS) remains a significant challenge. Herein, we introduce high-performance photoresists based on single-component self-immolative polymers (SIPs) with inherent signal amplification via cascade degradation. These SIPs function as dual-tone photoresists under both EB and EUV lithography, with performance primarily determined by the exposure dose. Lithographic evaluations show that discrete SIPs provide significant improvements over disperse counterparts, achieving higher resolution and reduced LER. Specifically, a discrete SIP with a DP of 12 produces a line-space pattern with a resolution of approximately 18 nm and an LER of 1.8 nm, compared to 21 nm resolution and 2.5 nm LER for disperse SIPs. Additionally, these SIP-based photoresists, enriched with aromatic structures, exhibit excellent etch resistance. The single-component nature and potential to address the RLS trade-off underscore the promise of discrete SIPs for EUV lithography.