EPFL'S CHARGE-BALANCED GAN TRANSISTOR HITS 3,400 VOLTS, 5X TODAY'S COMMERCIAL PARTS

Summary from the TLDR Hardware newsletter

Pushing gallium nitride to higher voltages usually causes charge to pile up in one spot when the transistor switches off, triggering electrical breakdown. EPFL's POWERlab fixed this by engineering an additional layer that produces a sheet of mobile holes nearly matching the electron sheet GaN naturally generates, letting the two charges cancel out so the electric field spreads evenly instead of spiking, all from the material's own polarization rather than temperature-sensitive doping. The result: diodes breaking down above 3.9 kV and transistors sustaining 3.4-3.5 kV, more than 5x the rating of many commercial GaN devices, holding up at 125°C with under 15% resistance drift during repeated high-voltage cycling.