Diamond Foundry Grows First 200mm Single-Crystal Diamond Wafer

Diamond Foundry has produced the world's first 200mm single-crystal diamond wafer, a milestone the company says brings diamond into wafer-scale production for semiconductor cooling. The sample remains unpolished, so chipmakers cannot use it yet. Still, the achievement is real, and the company is already eyeing 300mm wafers before 2030.

Diamond conducts heat at least five times better than copper, according to figures cited for the material. That property matters because AI chips now generate heat faster than conventional packages can remove it. A 200mm wafer matches the substrate size that fabs still use for older process nodes; a 300mm version would match what leading-edge fabs run today.

Why single crystal rather than polycrystalline?

Most lab-grown diamond is polycrystalline, which is easier to make but performs worse. Diamond Foundry grew its wafer as one high-quality single crystal, the harder route by far. The result combines extreme thermal conductivity with electrical insulation, a pairing that should suppress hotspots under high-power silicon. The company stated plainly on its website: "Single-crystal diamond has entered the wafer-scale era."

The firm, founded in 2012, credited scientists who have worked on the scale problem since the early 2000s. CEO Martin Roscheisen called the wafer "one of those milestones that once seemed almost impossible," adding: "It is the accumulated result of countless experiments, failures, inventions, rebuilt machines, and insights over more than a decade."

A company graph now suggests a 300mm SCD wafer is possible before 2030. That claim is a roadmap, not a product. The 200mm sample itself still needs polishing and further processing before it qualifies for fab use.

Who else is chasing diamond cooling?

Diamond Foundry is not alone in betting on synthetic diamond for thermal management:

• Akash Systems secured $18.2 million in CHIPS Act funding in 2024 to produce gallium nitride fused with synthetic diamond, a combination it claims cuts temperatures by 20 degrees Celsius.
• De Beers Group, better known for African diamond mines, is developing a copper-plated diamond composite for AI, high-performance computing and GaN RF devices.
• Frore Systems, known for solid-state cooling, is working on diamond-infused water-cooling cold plates for Nvidia's next-generation AI GPUs.

The pattern is consistent. As GPU power climbs, copper and liquid cooling alone are losing headroom, and materials with higher conductivity command attention.

One backer framed the effort in personal terms, saying: "Stefan and Martin pursued this goal for 25 years. There are very few examples in technology of someone sticking to a really hard scientific challenge with that level of perseverance." The same statement declared that the first D200mm wafer "makes D300mm predictable as well" — a confident claim, though polish, yield and cost remain untested at scale.

For now, the 200mm wafer is a demonstration, not a shipping product. Whether diamond reaches volume AI packages depends on the mundane work of polishing, bonding and pricing. If the 300mm roadmap holds, Diamond Foundry will have matched leading-edge wafer sizes with a material copper cannot rival.