What Ten Years of Photochemical Purification Taught Us About Preventing Lithography Defects

White Paper

Over the past decade, efforts to reduce lithography defects have tracked with EUV scaling in high volume manufacturing, revealing a shifting boundary of what limits yield. Particles remain critical, but additional impurities have proven just as consequential, with dissolved metals, polymer interactions, and complex chemical reactions emerging as key contributors to defectivity. In parallel, purification technologies advanced to address each newly exposed sensitivity, evolving from particle removal to ultra-low metal control, then to managing polymer interactions and chemical stability. This progression reflects both scaling and purification evolution, demonstrating how targeted purification technologies address diverse defect sources while moving control upstream to the conditions set during purification.