A research team at Xi'an Electronic and Technology University led by academician Hao Yue and Professor Zhang Jincheng says it has overcome a persistent thermal-management bottleneck in gallium nitride (GaN) radio-frequency chips by replacing “island-like” interfacial contacts with atomically flat aluminum‑nitride (AlN) thin films. The approach yields dramatic gains in microwave power density: the group reports 42 W/mm in the X‑band and 20 W/mm in the Ka‑band, figures the university says outperform comparable international devices by roughly 30–40 percent.
Thermal dissipation has long constrained attempts to push GaN devices to higher output. GaN transistors can handle large electric fields and high temperatures, but microscopic roughness and incomplete contact at material interfaces create thermal bottlenecks that limit continuous power and reliability. By engineering an atomically smooth AlN layer at the junction, the team reduced thermal resistance at the interface, enabling higher steady‑state power extraction without catastrophic heating or premature failure.
The practical consequences are immediate and wide‑ranging. Higher power density at unchanged chip area translates into longer radar detection ranges, stronger and farther reach for base‑station transmitters, and smaller or lower‑power phased arrays for satellite communications. The X and Ka bands cited in the release are widely used in military and commercial radar and in satellite links, so the performance gains map directly onto capabilities prized by telecom operators, satellite constellations and defence contractors.
Important caveats remain. The announcement stems from university research and does not yet describe mass‑production yields, long‑term reliability data, or integration with existing GaN supply chains and foundry processes. Scaling a laboratory film‑growth method to full wafer throughput can expose new defects, and commercialization will require resolution of manufacturing, packaging and testing challenges. The work does, however, strengthen a key piece of China’s roadmap toward domestic RF component capability for 5G/6G infrastructure, satellite internet and other strategic sectors.
The team links the challenge they addressed to a longstanding materials nucleation problem that has resisted full resolution since related nucleation advances were recognised by a Nobel Prize in 2014. Whether the university’s film technology becomes a broadly adopted industry standard will depend on independent verification, replication by commercial partners and the economics of integrating AlN films into existing GaN device stacks.
If sustained in production, the advance could shift competitive dynamics in high‑power RF semiconductors. Higher native power density reduces the need for expensive cooling solutions and could make GaN‑based systems lighter, more energy‑efficient and cheaper to operate at scale. For China this would be strategically useful as the country looks to lessen dependence on foreign suppliers for critical RF components that sit at the intersection of civilian telecoms and military electronics.