China Just Punches Through the EUV Stranglehold

The Bite That Didn’t Kill

In 2019, the Trump administration blocked exports of EUV lithography tools from ASML to China. The semiconductor industry breathed easier. The logic was simple: you cannot build cutting-edge memory without the world’s most precise printing presses. China would be stuck making commodity chips while the West raced ahead.

The assumption held for seven years. Then it unraveled.

According to reports from DigiTimes and other outlets, China’s largest DRAM maker, ChangXin Memory Technologies (CXMT), has begun small-scale production of HBM3E chips — the fifth generation of high-bandwidth memory, the same category of component that powers the world’s most powerful AI accelerators. Alibaba’s T-Head and Cambricon are already running validation tests. Mass production is expected as early as next year, with Huawei’s next-generation Ascend AI chips identified as the first major customer.

The strategic wound the US thought it inflicted has closed. And the scar tissue is dangerous.

How China Sidestepped the Ban

The EUV embargo was never going to be an absolute wall. It was a shortcut block, not a border fence.

Chinese engineers pivoted to Deep Ultraviolet (DUV) equipment — older, more available tools — and used multipatterning, a technique that layers multiple exposures to achieve finer feature sizes. It is slower. It is more expensive. It lowers yields. But it works.

The result is not parity. Yet. SemiAnalysis estimates CXMT’s HBM3 eight-stack yield at roughly 25 percent — a fraction of what Samsung and SK Hynix achieve. HBM3E yields will likely be lower still. But the trajectory matters more than the snapshot.

Industry assessments place the technology gap between China and Korea at approximately three years now, down from four or five just a couple of years ago. At that pace, the psychological advantage — the certainty that Korea would always stay ahead — begins to erode.

The NAND Front Opens Too

HBM gets the attention because it feeds AI. But the NAND side of China’s memory push is quietly reshaping a different market.

Yangtze Memory Technologies (YMTC) has built its own stacking architecture called Xtacking and developed NAND flash with over 300 layers. It has stabilized mass production yields at the 200-plus-layer level and climbed to third place in global NAND market share. More critically, YMTC holds 119 core patents on wafer-to-wafer hybrid bonding — the key process for building ultra-high-layer stacks above 400 layers.

The gap in NAND between China and Korea is now estimated at less than a year. YMTC has publicly declared it will overtake Samsung and SK Hynix in NAND by the end of next year.

Meanwhile, CXMT is moving into mainstream DRAM at scale. Its 17-nanometer DDR5 yield sits at around 90 percent, just two percentage points behind Samsung’s 92 to 93 percent. The company is also preparing to mass-produce LPDDR6 memory for Xiaomi’s upcoming foldable phone. With DRAM supply constrained globally, even Apple is reportedly considering Chinese-sourced generic memory as an alternative.

Who Wins, Who Loses

The immediate loser is clear: South Korea’s semiconductor exports. Memory chips are Korea’s single largest export category. Samsung and SK Hynix built their dominance on staying several generations ahead of anyone who might challenge them. A three-year gap is a luxury they have not had to defend against before. Three years is long enough for a competitor to enter the market, establish a customer base, and keep improving.

Huawei benefits most directly. Chinese AI chipmakers have been starved for HBM — the bottleneck that has constrained Ascend and other domestic GPU programs. Domestic HBM supply, even at modest yields, removes that constraint and lets China build AI infrastructure with less exposure to US sanctions.

Global AI buyers face a second source of supply. That is not inherently bad. But it is a geopolitical complication. The US has been careful to pressure allies to restrict semiconductor technology flowing into China. A viable Chinese HBM industry makes that enforcement exponentially harder — especially when Western cloud providers themselves are negotiating with CXMT on commodity memory.

China wins a strategic buffer. Korea faces a margin squeeze.

The Customization Play

There is one lever Korea still holds, and Samsung and SK Hynix are already pulling it.

The memory market is splitting. Generic DRAM and NAND are becoming commoditized — exactly where China is gaining ground fast. But the high-value niche is shifting toward customized memory. Big tech companies increasingly want HBM tuned to their specific chip architectures, not off-the-shelf parts. Samsung has responded with zHBM, a custom-configuration product line. SK Hynix is pursuing a parallel strategy with HBF (high-bandwidth flash).

The race is no longer just about who can make HBM. It is about who can make HBM that fits a particular AI accelerator’s interconnect design. That requires deeper co-development with chip designers — a relationship built over years, not months. Korea’s advantage here is institutional, not just technical.

But institutional advantages decay. China is funding this fight at a scale Korea cannot match. The state is directing resources through national R&D roadmaps that treat semiconductor self-sufficiency as a matter of national survival. That commitment does not flip on and off with election cycles.

What Comes Next

The EUV ban was always going to be temporary in its effectiveness. The question now is how quickly China closes the remaining gap and whether Korea can leapfrog into the customization tier before that happens.

The most likely scenario is a two-track memory world. China supplies its domestic AI ecosystem with HBM and NAND at diminishing quality levels — sufficient for most training and inference workloads, increasingly competitive on price. The West continues to push the frontier with next-generation HBM variants. The gap narrows year by year.

For Korea, the risk is not losing the top spot overnight. It is being squeezed in the middle — outcompeted on price by Chinese generic memory, while the premium customization segment becomes a narrower and narrower addressable market.

The 2019 EUV ban was supposed to lock China out. Instead, it forced China to find a harder, uglier, more expensive path that still leads to the same destination. That is the lesson the semiconductor industry is only now processing.