EPFL researchers develop high-voltage gallium nitride power chips

Researchers at EPFL’s POWERlab have developed a new class of gallium nitride (GaN) power-device design known as an intrinsic polarization superjunction (iPSJ). This technology addresses a major limitation in GaN electronics, which typically break down at voltages between 600 and 650 V.

By utilizing GaN’s natural polarization properties rather than relying on chemical doping, the team engineered layers to create both a two-dimensional electron gas (2DEG) and a two-dimensional hole gas (2DHG). This charge balance prevents excess charge from accumulating during switching, allowing the electric field to spread evenly across the device.

Testing demonstrated that the Schottky barrier diodes achieved breakdown voltages exceeding 3.9 kV while maintaining low on-resistance. The devices also remained stable at temperatures up to 125°C. This advancement could enable more compact and efficient power conversion for electric vehicles, renewable energy systems, and AI infrastructure.