SK hynix said it is advancing its use of extreme ultraviolet (EUV) lithography for the mass production of next-generation DRAM, with high-numerical-aperture (High-NA) EUV equipment introduced in the second half of 2025 and related research and development beginning in 2026. The memory maker is also adopting phase-shift mask (PSM) technology and other process materials to improve EUV performance as demand rises for higher-capacity, higher-performance chips.