Diamond Foundry, a lab-grown diamond company, says it has made the first single-crystal diamond wafer measuring 200mm across, roughly the size older chip factories use for silicon. The company wants diamond to take heat away from AI processors, which now run hot enough to limit how fast they can go.
Diamond conducts heat far better than most materials. It is estimated to move at least five times more heat than copper, while staying an electrical insulator, so it can sit against a chip without shorting anything. That combination is why chip designers keep returning to it as power per processor climbs.
The difficulty has always been size. Polycrystalline diamond is easy to make in large sheets but conducts heat less well, and a single-crystal piece this large was widely thought out of reach. Diamond Foundry’s wafer page now lists a world-first D200 diamond wafer, and the company shows a grey 200mm disc held in gloved hands.
Chief executive Martin Roscheisen credited hundreds of engineers and scientists at the firm, and said the result came after years of failed experiments and rebuilt machines. A statement quoted in the announcement describes two people at the firm as having chased the goal for 25 years, and says the 200mm result makes a 300mm wafer, the size used for leading-edge chips, predictable. A chart from the company puts that before 2030.
Diamond Foundry’s page also lists a D100, the 100mm single-crystal diamond it announced in 2023, so the new disc doubles the width of its own earlier milestone. The company was founded in 2012 and acknowledged in its announcement that other scientists had been working on the size problem since the early 2000s.
The thermal case rests on hotspots. An AI processor does not heat evenly: a few dense blocks of transistors run much hotter than the rest, and a spreader that carries heat sideways quickly lets the chip run harder before it has to slow down. A single crystal, with no grain boundaries to scatter heat, is what makes diamond good at that job.
The disc on show is unpolished, so it still has to go through finishing before a chipmaker could use it. Diamond Foundry has not said when customers could receive wafers or what they would cost.
It is not alone in chasing diamond cooling. Akash Systems received $18.2 million in US CHIPS Act funding in 2024 to make gallium nitride chips on synthetic diamond, which it says lowers temperatures by 20 degrees Celsius. De Beers is developing a copper-and-diamond composite for cooling AI and high-performance computing parts, and Frore Systems is making diamond-infused water-cooling cold plates for Nvidia’s next AI GPUs.
For now this is a materials milestone, not a product. Anyone buying a graphics card or laptop will not see diamond inside for some time, and the first customers are likely to be makers of AI accelerators in data centres.
