2026 Volume 39 Issue 2 Pages 67-84
Over the past twelve years, imec has played a central role in advancing extreme ultraviolet (EUV) lithography through the enablement of tin-based metal-oxide photoresist (MOR) technologies. This review traces the evolution of MOR materials from their early exploration in 2014 to their recent deployment in high NA EUV patterning. Key milestones include the first demonstrations of fab-compatible spin-on MORs in 2016, the integration of 28 nm pitch spin-on MOR patterning in a 7 nm technology node module in 2021, and the emergence of dry (deposited) MOR system that broadened design space and process tunability. The program reached a new inflection point in 2024 with the first single exposure down to an 16 nm pitch pattern using high NA EUV lithography, made possible by operando studies that revealed how the reactions proceed and guided mechanism-based improvements. These advances reflect a deep collaboration across imec’s ecosystem and illustrate how metal-oxide chemistry complements chemically amplified resist platforms. Although metal-oxide resists have seen initial adoption in high-volume EUV manufacturing, their broader implementation across both Low NA and High NA EUV lithography will require sustained collaborative innovation across the ecosystem coupled with rigorous process co-optimization.
