US BIS: 2021 Wassenaar Arrangement — Four Section 1758 Emerging Technologies (Ga₂O₃, Diamond, GAAFET ECAD, Pressure Gain Combustion)

Mechanism

BIS implemented four technology controls arising from decisions taken at the December 2021 Wassenaar Arrangement Plenary (42 member states), each qualifying as an "emerging and foundational technology" under ECRA Section 1758. The rule amends the CCL as follows:

1. Ultra-Wide Bandgap Semiconductor Substrates — Gallium Oxide (Ga₂O₃)

• ECCNs revised: 3C001, 3C005, 3C006, 3E003
• Gallium oxide (β-Ga₂O₃) is an ultra-wide bandgap (UWBG) semiconductor (Eg ~4.7 eV) capable

of operating at voltages and temperatures well beyond existing GaN (3.4 eV) and SiC (3.2 eV) devices. Key applications include: high-voltage power electronics (10 kV+), radiation-hard electronics for space/nuclear, solar-blind UV photodetectors, and directed-energy weapons.

• Epitaxial layers and bulk substrates added to CCL; related development/production technology

controlled under 3E003.

2. Ultra-Wide Bandgap Semiconductor Substrates — Diamond

• ECCNs revised: 3C001 (.f), 3C005, 3C006, 3E003
• Diamond (Eg ~5.5 eV) offers extreme thermal conductivity (~2,000 W/m·K), radiation hardness,

and breakdown voltage — relevant to military RF power amplifiers, radar, and high-power lasers. Control covers synthetic diamond wafers/substrates and diamond epitaxial layers used as semiconductor active material.

3. ECAD Software for GAAFET Integrated Circuits — ECCN 3D006 (new, effective 2022-10-14)

• Gate-All-Around Field-Effect Transistor (GAAFET) structures are the successor architecture to

FinFET below ~3 nm node. EDA/ECAD tools specially designed for RTL-to-GDSII implementation or power/timing/signal-integrity optimisation of GAAFET circuits are now controlled under new ECCN 3D006.

• The 60-day delayed compliance window (to 2022-10-14) allowed in-transit software licences to

be completed before the rule took effect for ECAD products.

• This is the first CCL classification directly targeting EDA software at an architectural node,

predating the October 2022 advanced chip rules. Affected vendors include suppliers of front-end design-flow tools targeting Samsung and TSMC 3 nm-class GAAFET fabs.

4. Pressure Gain Combustion (PGC) Technology — ECCN 9E003.a.2.e (new paragraph)

• PGC (e.g., pulsed or rotating detonation combustion) achieves thermodynamic efficiency gains

of 10–30% over conventional deflagration combustors in gas turbine engines. Development and production technology for combustors and components utilising PGC is now controlled.

• Applicable to: advanced fighter/bomber engine programmes, hypersonic air-breathing propulsion

(scramjet/RDE), and next-generation commercial turbofan development with military spin-on potential.

Downstream implications

• Semiconductor equipment and substrate suppliers shipping Ga₂O₃ or diamond wafers to non-NS1

destinations now require BIS export licences; China is a primary licence-required destination.

• EDA vendors (Synopsys, Cadence, Siemens EDA) with GAAFET-capable design tools must apply

ECCN 3D006 classification and obtain licences for covered software exports to NS:1 countries.

• Combined with the October 2022 advanced chip controls, this rule signals a systematic BIS

effort to close the full technology stack — from substrate materials to design software — for next-generation semiconductor manufacturing.

• PGC controls extend the CCL to combustion R&D for the first time at this level of specificity;

aerospace primes with international JV structures (e.g., CFM International, IAE) will need to re-screen technology-transfer arrangements with non-Wassenaar partners.

Open questions

• Whether TSMC's Arizona fab operations (US soil) trigger ECAD transfer controls back to Taiwan

for GAAFET design tools under domestic re-export rules.

• UK, EU and Japan Wassenaar members are expected to implement equivalent controls; timing and

transposition gaps (especially for EU dual-use regulation) create temporary licensing arbitrage.

• The diamond substrate control scope (only semiconductor-grade synthetic diamond, not gem

diamond) will require classification guidance as CVD diamond quality improves.