Deep ultraviolet (DUV) lithography

Deep ultraviolet (DUV) lithography patterns semiconductor wafers using 248-nanometre krypton-fluoride or 193-nanometre argon-fluoride light. Dry and immersion systems serve many process generations, including mature-node production and some advanced fabrication using multiple patterning steps. DUV became a control focus when restrictions expanded beyond EUV.

Function

DUV tools project circuit patterns through optics onto photoresist. Immersion systems place purified water between the final lens and wafer to improve numerical aperture. Multiple exposures and process steps can extend 193-nanometre immersion lithography to smaller features, but add masks, alignment demands, cycle time and opportunities for yield loss. Toolmaker, fab operator, materials supplier and licensing authority therefore occupy distinct roles. ASML's product information establishes system function; control status comes from the applicable regulation and licence decision.

Strategic significance

DUV can provide a partial substitute where EUV is unavailable, although additional patterning can reduce throughput and raise cost. A teardown may identify a chip's apparent process class, but it does not identify the lithography tools used, the fab's yield or the legal route by which any equipment was acquired. These evidentiary limits matter because a technical demonstration, repeatable commercial production and a proven control breach are different propositions.

Control or weaponisation history

Restrictions moved in sequence with the Multilateral chip-control coalition. Following the unilateral US United States advanced-computing and semiconductor controls on China (2022-present), the Dutch government introduced national licence requirements for specified advanced semiconductor-manufacturing equipment. A measure took effect on 7 September 2024, followed by additional controls effective 1 April 2025 that covered further equipment, including specified measurement and inspection technology. These measures show how a control boundary can expand from EUV to selected DUV and adjacent process tools. They do not establish a total ban, a particular licence outcome or the commercial effect on any supplier without transaction-level evidence.

Current status and evidentiary limits

Dutch controls effective on 7 September 2024 and 1 April 2025 require case-by-case licences for specified advanced semiconductor-manufacturing equipment. They do not constitute a total ban on every DUV system, spare or service. The legal question turns on the listed equipment, destination, end user and licence decision. Teardown evidence can establish that a device contains a chip of an assessed process class, but not which tool produced it or whether an export breached the rules.

Substitution is also process-specific. A fab may use DUV multi-patterning for some layers without reproducing the cost, yield or throughput of an EUV-based process. Installed tools, new exports, servicing, software updates and spare parts are separate transactions and may receive different legal treatment.

See also

Extreme ultraviolet (EUV) lithography · Semiconductor chokepoint · Semiconductor and lithography equipment denial · Multilateral chip-control coalition · United States advanced-computing and semiconductor controls on China (2022-present) · Legacy and mature-node chips · Chokepoint effect · Economic statecraft · Photoresist and specialty chemicals

Sources

• ASML DUV lithography.
• Netherlands, expanded semiconductor-equipment controls, 2024.
• Netherlands, additional controls effective April 2025.
• EAR part 742.