European AESA radar: who supplies the T/R module chain?

United Monolithic Semiconductors (UMS) supplies semiconductor components and foundry services; HENSOLDT has announced an agreement to source UMS components for radar transmit/receive modules. Fraunhofer IAF contributes research, fabrication and small-series capability. MACOM’s French semiconductor centre adds manufacturing in Europe under a US parent. These roles need separate assessment from complete-module production and radar-system integration.

Semiconductors and radar-module integration

A transmit/receive (T/R) module in an active electronically scanned array (AESA) radar depends on a chain of specialised suppliers. Modules should not be treated as interchangeable purchases. The supply map needs to distinguish materials and epitaxy, semiconductor design and fabrication, packaging, module assembly and radar integration. A business that offers a fabrication process is not necessarily offering an independently qualified complete module. For a sourcing or investment team, the useful starting point is the exact deliverable and production step for which a counterparty is being considered.

United Monolithic Semiconductors is a commercial semiconductor supplier. Its main locations are in France and Germany, and it describes GaAs and GaN integrated-circuit products, custom solutions and foundry services. Those capabilities support different customer relationships: purchasing a component, commissioning a design and using a foundry process are not equivalent arrangements. The buyer should establish which process and site underpin the offered part, what is qualified and how production commitments are allocated.

A direct link to programme demand is visible in HENSOLDT’s March 2026 agreement with UMS. HENSOLDT announced supply of 900,000 GaN semiconductor components by 2030 for use in its radar transmit and receive modules, particularly within the Spexer family. The disclosed unit is semiconductor components. It is not 900,000 complete modules or radars. This distinction prevents a substantial supplier agreement from being misused as an estimate of total European module demand.

Research capability and manufacturing ownership

Fraunhofer IAF occupies a different position. Its published capabilities span GaN research, circuit design, fabrication, modules and small-series work. Such capabilities can help develop and industrialise processes, but a research offering does not by itself establish high-volume capacity available to a defence procurement programme. The diligence task is to identify the handover from demonstrator to qualified serial supplier, including process transfer, intellectual-property rights, repeatability and the organisation responsible for production assurance.

MACOM's European Semiconductor Center announcement records completion of its acquisition of OMMIC's key manufacturing assets and capabilities in France. This is a European-located industrial resource within a US-headquartered group. Production geography and corporate control should therefore remain separate fields in the supplier map. Neither fact alone resolves availability, export permissions or eligibility for a particular European funding instrument. Those conclusions require examination of the actual entity, product, contracts and applicable rules.

Second-source qualification and usable capacity

The middle of the chain is especially important for substitution. Availability of an alternative semiconductor die does not establish that an existing module can use it without redesign, packaging changes or renewed qualification. Thermal interfaces, assembly processes and testing belong in the industrial assessment, even when the public material focuses on semiconductor performance. The practical question is how much work and time a second source must reproduce before it can supply an accepted deliverable. A catalogue match is only an initial screening signal.

Capacity claims should be tied to a specific process and commercial commitment. Wafer size, cleanroom area or a new line can indicate investment, but none alone establishes accepted output per period. Yield, testing capacity, qualification status and competing demand affect the usable result. Public information often leaves these points unresolved. An analyst should preserve that uncertainty and request the relevant supplier evidence instead of deriving a module production estimate from unrelated semiconductor or radar figures.

The resulting map should show each counterparty's role, site, ownership, qualified deliverable and route to the customer. Long-term offtake, process access and rights to maintain or modify designs determine whether the relationship can support a programme through production and sustainment. This makes the map useful for commercial decisions: it identifies the specific dependency to investigate and the evidence needed to resolve it, while avoiding unsupported rankings of European technological sovereignty or aggregate module supply. The map should be refreshed when ownership, processes or programme commitments change.