Modern radar performance depends on active electronically scanned arrays, thousands of electronic components, and increasingly powerful processing systems. But trace that technology far enough upstream, and the supply chain eventually reaches another industry altogether: critical materials.
Gallium, arsenic, indium, and specialized ceramics all enter the chain at different stages. Looking inside a modern radar reveals a broader industrial reality: control over a weapons system starts long before final assembly.
Behind the radar: millions of components
The U.S. AN/SPY-6 provides a particularly well-documented example. Developed by Raytheon for the U.S. Navy, the active-array naval radar is built around Radar Modular Assemblies, or RMAs, which can be combined to create arrays of different sizes depending on the ship and mission.
In September 2025, Raytheon reported that it had produced more than 2,000 RMAs, requiring approximately 50,000 transmit/receive modules, 150,000 RF heads, and around 1.8 million microwave chips. The chain starts at the chip level in a GaN foundry and extends all the way to the finished radar array.
These figures show why material criticality has little to do with how much of it ends up in the finished system.
In an AESA, or Active Electronically Scanned Array, large numbers of transmit/receive elements are electronically controlled to form and steer the radar beam. Their performance depends directly on the semiconductors used to generate, amplify, and receive radio-frequency signals.
Gallium at the core of the array
Gallium is not installed directly into the radar. It is processed into compounds including gallium arsenide, or GaAs, and gallium nitride, or GaN.
GaAs has long played an important role in military RF components. GaN, meanwhile, can operate at high power and voltage levels under demanding thermal conditions. This gives engineers greater flexibility in balancing power output, efficiency, array size, cooling requirements, and overall performance.
The technology is now used across a wide range of systems, including the U.S. SPY-6, Thales’ Ground Master 400 Alpha, several Saab radars, and Mitsubishi Electric’s Japanese FPS-3ME.
But gallium is only one part of the radar supply chain. Arsenic is used in GaAs, indium can be found in some advanced RF architectures, and silicon remains ubiquitous in computing and control functions. Radar performance also depends on materials used in thermal management, power electronics, and supporting RF hardware.
The U.S. Government Accountability Office, or GAO, has highlighted how difficult some of these materials can be to replace. For certain defense applications, alternatives to semiconductor technologies based on gallium, germanium, arsenic, or indium could take ten years or more to reach sufficient maturity. Recycling is also difficult because these materials are used in very small quantities and are widely dispersed across individual components.
From the radar to the raw material
To understand where the real vulnerability lies, the entire supply chain has to be traced upstream. Gallium is primarily recovered as a byproduct of processing bauxite and certain zinc ores. That is where the supply chain becomes far more geographically concentrated.
China accounts for approximately 99 percent of global production of low-purity primary gallium. The United States, by contrast, has a highly advanced radar and RF-semiconductor industry while remaining dependent on imports for much of its raw-material supply.
That distinction matters: relying on China for the primary material does not mean relying on China to manufacture the radar.
Between those two stages lie purification, semiconductor material production, wafer fabrication, integrated circuits, modules, and final array integration. The United States retains significant capabilities across these higher-value stages.
Japan has a similar industrial profile. Mitsubishi Electric has mastered GaN modules and their integration into AESA radars without having comparable independence in raw materials. Europe relies on a more distributed industrial base, with capabilities spread across several countries and defense companies.
Elsewhere, countries are trying to bring more of the supply chain under domestic control. India is developing AESA radars alongside GaN and MMIC technologies. Singapore, despite lacking a major domestic mineral base, is building national capabilities in GaN, MMICs, and wafer fabrication for defense applications.
Brazil represents almost the reverse situation: a significant resource base combined with a developing domestic radar industry, but without necessarily controlling every intermediate stage of the RF-electronics supply chain.
Industrial autonomy is not binary. A country may control the raw material without mastering semiconductor fabrication, or integrate advanced radars while remaining dependent on upstream suppliers. Raw materials, semiconductor processing, RF components, and system integration represent distinct layers of industrial control.
The Russian paradox
Russia’s vulnerability lies elsewhere in the chain. The country has a substantial mineral-resource base and an industry capable of producing complex radar systems. Its dependencies emerge further downstream.
A 2025 study by the Royal United Services Institute, or RUSI, examining Russian air-defense production documented dependencies involving certain microelectronics, processed materials, and industrial equipment. It identified beryllium oxide ceramics, in particular, as critical to Russian radar production.
Russia retains the ability to produce modern radars, but access to raw materials does not remove dependencies in advanced processing, components, and production equipment.
Where the U.S. vulnerability appears mainly at the far upstream end of the supply chain, Russia’s vulnerabilities are more likely to emerge in intermediate technological stages.
Can China stop western radar production?
China’s dominance of gallium production could suggest that Beijing holds an effective “off switch” for Western radar manufacturing. But that leverage has limits.
Chinese export restrictions introduced since 2023 have shown that this concentration can be used as a strategic tool. But restricting exports of primary gallium would not bring Western production lines to an immediate halt.
Stockpiles, refining capacity outside China, recovery of industrial scrap, and alternative suppliers all provide some resilience. More importantly, much of the technological value wafer fabrication, RF integrated circuits, MMICs, modules, and radar integration remains controlled elsewhere.
The real vulnerability is cumulative. Establishing new production and refining capacity takes years, while replacing the materials used in semiconductor technologies offers no quick fix.
A prolonged dependency could therefore make it harder and more expensive to raise production rates just as military demand is increasing.
A radar begins long before the antenna
A modern radar is not simply the product of a major defense company designing an antenna, software, and electronic architecture. Its production depends on a series of far less visible capabilities: extraction, refining, semiconductor materials, wafers, RF microelectronics, thermal management, transmit/receive modules, and ultimately system integration.
Strategic autonomy increasingly depends on that industrial depth.
As militaries rebuild stockpiles and industry pushes for higher output, those dependencies become operationally relevant once production scales up. A vulnerability that remains almost invisible when only a few dozen systems are being built can become a bottleneck when much larger numbers have to be produced faster and sustained over several years.
Radar production highlights a less visible side of rearmament: producing more systems depends not only on assembly capacity, but on the depth and resilience of the industrial supply chain behind them.
In that supply chain, a few grams of critical material can matter more than tons of steel.
