➀ Researchers at the Paul Scherrer Institute (PSI) have achieved 5 nm half-pitch line/space patterns using 13.5 nm EUV light, surpassing the theoretical maximum resolution of ASML’s high-NA EUV tool. ➁ The technique used, EUV interference lithography (EUV-IL), involves making two EUV beams interfere to create periodic images, previously achieving patterns down to 6 nm half-pitch. ➂ The study concludes that photons are not the limiting factor for resolution at this scale, shifting focus to developing new photoresist materials and optimizing existing platforms.