Gallium nitride (GaN) is a wide bandgap semiconductor material derived from gallium and nitrogen.
Used in LEDs since the 1990s, it is known for its robust hexagonal crystal structure and can handle larger electric fields in a compact form factor compared to silicon, allowing for faster switching.
Apple's first GaN charger was for the 16-inch MacBook Pro in 2021, and if you have an iPhone 15, chances are you're using a GaN charger.
Measuring conditions inside a reactor
It turns out that GaN might be even more impressive than previously thought. Sensors used to monitor a nuclear reactor's cooling system often have accuracy problems due to radiation. Researchers at the Department of Energy's Oak Ridge National Laboratory (ORNL) found that combining the sensors with high-performance electronics made from GaN solved the problem.
ORNL's materials science team discovered a GaN transistor that maintained operations near the core of a nuclear reactor at The Ohio State University. “We're showing that it's ideally suited for this neutron environment,” said Kyle Reed, principal investigator at ORNL. This breakthrough is important for nuclear facilities, where early monitoring of conditions can prevent equipment failures and reactor downtime.
Current sensor data processing relies on silicon-based electronics connected by long wires, which creates noise and reduces accuracy. “Our work makes measurement conditions inside an operating nuclear reactor more robust and accurate,” Reed said.
ORNL researchers irradiated GaN transistors for three days at temperatures up to 125 degrees Celsius. Remarkably, they withstood the conditions, withstanding at least 100 times the radiation dose that standard silicon devices could withstand.
Microreactors, which generate smaller power outputs but require compact and rugged components, could benefit from GaN transistors, which could be deployed at sites such as military bases or disaster zones.
Despite being commercially available for about a decade, GaN has untapped potential. “We are opening up different secondary avenues for the use of gallium nitride so that we can begin to create more reasonable market demand for investment, research and workforce development for subclasses of electronics beyond consumer grade,” Reed said.
