China has stockpiled 343 immersion DUV lithography tools to support advanced chipmaking, according to a report highlighted by Tom's Hardware. Of those machines, 270 are ASML scanners that the report claims can produce 7nm-class processors without access to sanctioned EUV equipment.

The figure, if accurate, describes one of the largest single-country install bases of immersion lithography outside leading-edge fabs in Taiwan and South Korea. Immersion DUV scanners — which use water between the lens and wafer to print finer features — remain export-legal to China in most configurations, unlike ASML's EUV machines, which the Dutch government has never licensed for shipment to Chinese customers.

Why does the stockpile matter?

The report's central claim is quantitative: 270 ASML immersion tools represent enough multipatterning capacity to sustain 7nm production. Multipatterning — printing a layer in several exposure passes — is the technique SMIC used to fabricate Huawei's 7nm-class Kirin 9000S processor in 2023, demonstrating that DUV-only routes to advanced nodes exist, at the cost of lower throughput and higher per-wafer expense than EUV-based production at TSMC or Samsung.

A 343-tool stockpile implies China has hedged against the next round of restrictions. Since 2023, US and allied export controls have progressively tightened. The Netherlands began requiring licenses for ASML's most advanced immersion systems — the NXT:2000i series and above — in 2024. Reports of accelerated Chinese orders ahead of each regulatory deadline have circulated since the first restrictions were drafted.

What can 343 immersion tools actually build?

The report frames the stockpile around 7nm capability, not parity with leading-edge EUV users. That distinction matters commercially:

• 7nm-class logic: reachable via DUV multipatterning, as SMIC demonstrated — but with yield and cost penalties that constrain competitiveness outside captive demand.
• 5nm and below: DUV routes grow increasingly expensive and slow; the report does not claim this stockpile enables such nodes.
• Mature nodes (28nm and above): immersion tools also serve these markets, where Chinese fabs face no comparable constraints and capacity is expanding fastest.

The remaining 73 tools in the 343-unit figure are not attributed to a specific vendor in the report summary, though Nikon has historically been the only other merchant supplier of immersion scanners.

Export-control context

Washington's October 2022 rules and subsequent updates targeted both the tools themselves and the Chinese fabs flagged as advanced-node producers. Equipment makers absorbed the impact unevenly: ASML's China revenue share climbed sharply in 2023–2024 as Chinese fabs rushed to absorb tool shipments before further restrictions landed, then declined in 2025 as backlogs cleared.

The report does not specify the purchase timeline for the 343 machines, so it remains unclear how many arrived before versus after licensing requirements took effect. That gap leaves room for analyst disagreement about how quickly China can convert stockpiled capacity into sustained advanced-node output rather than one-off demonstrations.

The strategic question ahead

Whether 343 immersion scanners translate into a durable 7nm supply base depends less on lithography than on the surrounding supply chain — DUV photoresists, metrology, and etch equipment — where Chinese domestic substitutes remain thinner. The report's claim positions China's DUV fleet as a floor under advanced-node capability; the ceiling will be set by how far multipatterning economics can stretch before domestic EUV alternatives, still unproven, arrive.