A team of scientists from Xidian University in China has developed a new supercooling technique for gallium nitride semiconductors, suggesting that it will improve military radar performance by roughly 40%.
With the promise of increasing the performance of military radars and future wireless networks, the new approach concentrates on one of the most challenging limits in high-power electronics: heat. While gallium nitride chips can handle high voltages and frequencies, overheating tends to limit their performance.
Source: Xu Hangchuan
As such, the scientists sought to address the issue at the materials level, designing new chips capable of operating under extreme power loads in the X and Ka frequency bands, thus leading to more powerful, compact radar systems for advanced aircraft and communications infrastructure.
According to the team, the X and Ka frequency bands are critical for modern fire control radars, satellite links and fast wireless data transmission. Specifically, this means radar systems can send stronger signals and detect weaker echoes without added size or weight.
Further, the team suggests that the improved thermal design enables radar systems to see farther while keeping the hardware compact. Similarly, this new method could also be used in mobile networks wherein the chips promise to extend signal coverage while reducing electricity consumption — an important issue for dense 5G and future 6G deployments.
The new approach particularly addresses the challenge affecting the bonding layer that joins different materials within a chip. Current manufacturing approaches rely on aluminum nitride as this intermediate layer. However, during growth, this material creates uneven islands — instead of a smooth film — where heat gets trapped, thereby increasing thermal resistance and degrading performance.
To remedy this, the team devised a method for precisely controlling how this layer grows, thus turning what was once a random process into a uniform one that reportedly cuts thermal resistance by about one-third when measured against conventional designs. This led to what the team suggests is improved power handling and heat dissipation.
The team detailed their work in the article, “High power density gallium nitride radio frequency transistors via enhanced nucleation in heteroepitaxy,” which appears in the journal Nature Communications.
