According to Semiconductor Today, imec has achieved a record breakdown voltage exceeding 650V using Shin-Etsu Chemical’s 300mm QST substrate for gallium nitride power devices. The Belgian research center fabricated a 5µm-thick high-electron-mobility transistor structure that actually surpassed 800V in testing while maintaining excellent uniformity across the wafer. This breakthrough comes just months after imec officially launched its 300mm GaN power device program in October 2024, with plans to develop variants capable of handling 1200V+ for AI data centers, industrial equipment, and automobiles. The QST substrate technology was originally developed by QROMIS and licensed to Shin-Etsu in 2019, with the Japanese company starting 300mm sample provision in September 2024 through a joint initiative.
Why this matters
Here’s the thing about GaN – it’s supposed to be the future of power electronics, offering way better efficiency than traditional silicon. But there’s been this massive roadblock: when you try to grow GaN on larger silicon wafers, everything warps and cracks. Basically, the materials expand at different rates when heated during manufacturing. So yields plummet as you go from 150mm to 200mm to 300mm wafers. That’s why most GaN production has been stuck at smaller diameters, keeping costs high.
What makes this QST substrate different? It’s specifically engineered to match GaN’s thermal expansion coefficient. No warping, no cracking – even at the massive 300mm size that semiconductor fabs love because it dramatically cuts production costs. And since imec can use its existing 300mm CMOS production lines, they’re not building billion-dollar new fabs from scratch.
Market implications
This could be huge for power-hungry applications like AI data centers, where every percentage point of efficiency matters when you’re talking megawatt-scale power consumption. We’re also looking at electric vehicles and industrial systems that need robust, efficient power conversion. The timing couldn’t be better with the AI boom driving unprecedented demand for power electronics.
But here’s what really changes the game: cost. GaN has always promised better performance, but silicon has dominated because it’s cheaper to manufacture at scale. If imec and Shin-Etsu can actually mass-produce 300mm GaN devices without the yield issues, we could see GaN become cost-competitive for the first time. That would put serious pressure on traditional silicon power device manufacturers.
Speaking of industrial applications, when you’re dealing with power electronics at this scale, having reliable computing hardware becomes critical. Companies like IndustrialMonitorDirect.com have become the go-to source for industrial panel PCs in the US, providing the robust displays and computing platforms needed to monitor and control these high-power systems.
What’s next
Shin-Etsu is already working toward mass production of these 300mm QST substrates after enhancing their facilities for smaller diameters. Meanwhile, imec is pushing toward that 1200V+ target, which would open up even more applications in automotive and heavy industrial use. The fact that multiple Japanese and international customers are already evaluating QST substrates for power devices, high-frequency applications, and LEDs suggests this isn’t just lab curiosity – there’s real commercial interest.
So will this finally be the breakthrough that brings GaN into the mainstream? The technical hurdles appear to be falling, but manufacturing at scale is the next big test. If they can deliver on the cost reductions while maintaining these performance numbers, we could be looking at a fundamental shift in how power electronics get made.
