To: BeenRetired who wrote (41831 ) 10/5/2025 11:11:53 AM From: BeenRetired 1 RecommendationRecommended By
Respond to EUV NAND? Yup.EUV has broken out of its original niche in leading-edge logic and is now actively used in DRAM, HBM, and NAND production , reshaping the memory landscape.Why EUV matters : It replaces complex multi-patterning steps, improving yield and reducing edge placement error—critical for DRAM scaling.EUV is used in the DRAM dies that make up HBM stacks. As HBM moves to HBM3E and HBM4 , EUV enables tighter pitches and lower power. SK Hynix and Samsung are leveraging EUV to meet OpenAI, Nvidia, and AMD demand for AI accelerators.SK Hynix and Kioxia/WD are deploying EUV in peripheral logic and CMOS under array (CUA) layers.EUV helps reduce die size and improve integration in 3D NAND , especially as layer counts exceed 300. Note : EUV isn't used in the vertical memory stack itself (which is etched), but in the control logic and interface layers.Not quite—Samsung’s 1c DRAM actually uses fewer EUV layers than originally planned. While EUV is still critical, Samsung reduced its EUV usage in 1c to improve yield and process stability. Initial Plan : Samsung originally intended to use 8–9 EUV layers in its 1c (sixth-generation 10nm-class) DRAM.Current Status : That number has been revised down to 6–7 layers , a ~30% reduction from the original roadmap.Reason for Reduction :Yield optimization : More EUV layers increased process complexity and defect risk.Cost control : Fewer layers reduce infrastructure burden and improve long-term cost competitiveness.Stability : EUV introduces challenges in downstream steps like etch and deposition, especially in DRAM’s tight pitch structures.Samsung’s 1d DRAM (7th-gen) is expected to be more EUV-rich than 1c, with a higher layer count and tighter geometries.Logic nodes (e.g., 3nm, 2nm) still use significantly more EUV layers than DRAM—often 20+ layers in advanced SoCs.pragmatic balance : using EUV where it delivers yield and patterning benefits, but not overextending it where it adds risk. EUV remains essential, but its deployment is being tuned per node and product type.you’re absolutely correct . When saying that Samsung’s 1c DRAM node uses “more EUV layers,” the comparison is to earlier DRAM nodes like 1a and 1ß , not to earlier internal drafts of 1c itself.“More EUV” means : Compared to 1a and 1ß , Samsung’s 1c DRAM integrates more EUV layers into its process flow.Not referring to : Early internal plans for 1c (which may have targeted 8–9 layers but were revised down to 6–7 for yield reasons).EUV adoption in memory means ASML’s tools are no longer logic-exclusive . It boosts tool utilization rates , making fabs more cost-efficient. It also means memory vendors are now part of the EUV Village , driving innovation in resist, pellicle, and inspection.
