Researched
Immersion Lithography
A film of ultrapure water between lens and wafer (proposed 2001-02, first scanner shown by ASML in 2003) raises the numerical aperture beyond 1.
Open in the interactive tree →Water bends light more than air, so the same 193 nm laser prints finer lines. Immersion scanners extended optical lithography by roughly a decade and were the last step before EUV.
Prerequisites
Unlocks
- EUV Lithography2019Immersion was the last optical step before EUV was needed
- 2 nm Chips & High-NA EUV2025Raising numerical aperture was already the lever used in immersion lithography