ASML Holding (ASML) shares climbed about 4% to $1,870.48 this week after the Dutch lithography equipment maker deepened its partnership with Samsung around High-NA extreme ultraviolet (EUV) technology, the most advanced lithography platform in volume chip production. Lithography is the patterning step that determines how small and densely packed a chip's transistors can be, and ASML is the only company in the world that builds EUV systems — which is why each adoption milestone carries weight across the entire industry. High-NA is the next iteration of that technology, widening the optics' numerical aperture from 0.33 to 0.55 to print even finer circuit features.

Under the September 8 agreement, the two companies will also jointly develop larger, 12-inch photomasks — the templates that carry circuit designs onto wafers. Conventional masks are 6-inch squares, so doubling the size would let a scanner cover more wafer area per pass and cut the number of exposures each wafer requires. Samsung plans to bring High-NA EUV into high-volume DRAM production by 2028, a step that extends High-NA beyond the logic-focused roadmaps of Intel and TSMC and into memory manufacturing.

That timeline marks a turning point for ASML. Until recently, High-NA machines were mostly viewed as expensive, experimental tools; they are now turning into genuine production equipment. No system-order totals or delivery timelines were disclosed alongside the Samsung announcement, leaving Samsung's 2028 DRAM date and TSMC's 2030 production start as the next concrete checkpoints for High-NA's move from experiment to volume production.

Customer Commitments Are Building

Intel offers the clearest validation to date. The chipmaker has processed more than one million wafers on ASML's High-NA systems and says key production metrics are meeting expectations. Intel already applies High-NA to select layers of its 18A manufacturing process — the kind of production-scale proof ASML needed.

TSMC is also in the picture. The foundry giant plans to adopt High-NA for high-volume production starting in 2030 — a commitment that eases doubts about long-term demand — and is working with ASML on the larger photomasks as well. The goal is better scanner productivity and lower chip production costs. As AI chip designs grow more complex, TSMC expects more layers to require High-NA tools, and each additional layer translates into more demand for ASML's priciest equipment.

ASML, meanwhile, is preparing supply. The company plans to boost 2027 low-NA EUV capacity by 30%, up from around 65 systems in 2026. Its 2027 EUV capacity was already close to fully booked as of July, giving ASML a clear runway to turn orders into actual deliveries.

Risks Still Linger

China remains the biggest wildcard. A Reuters report found that domestically built immersion DUV systems have entered production in China. DUV, or deep ultraviolet, is the lithography generation that precedes EUV and still underpins much of the industry's mainstream chipmaking. Those machines still sit far behind ASML's technology, but if they keep improving, China could lean less on foreign equipment over time. The stakes are considerable: China accounted for about 16% of ASML's first-half 2026 sales, and export controls already block the company from selling EUV and some advanced DUV machines there.

Valuation is another factor to watch. ASML trades at more than 32 times forward earnings, which leaves little room for missteps. Shares are also sitting roughly 48% above a GF Value estimate of about $1,270, meaning any delay in High-NA adoption could hit the stock harder than usual.

Wall Street, however, remains bullish. Analysts hold a Strong Buy consensus on the stock, based on six Buy ratings over the past three months. The average price target sits at $2,391.80, implying about 29% upside from current levels.