Scientists grow world’s largest diamond crystal in breakthrough that could stop AI chips overheating

American technology firm Diamond Foundry has produced an eight-inch diamond that could help make computers faster and more powerful, with a multi-billion-euro project in Spain aiming to bring the technology into mass production

Scientists have grown a giant diamond crystal that could help stop powerful AI computer chips overheating, potentially paving the way for faster, more reliable computers.

American technology company Diamond Foundry says it has created the world’s first single-crystal diamond measuring 200mm – almost eight inches – across, overcoming a problem that has frustrated researchers for 25 years.

The breakthrough could eventually allow diamond to be used in computer chips on an industrial scale, helping tackle the enormous heat generated by the processors powering artificial intelligence.

The company believes the discovery could help overcome one of the biggest challenges facing AI developers, whose increasingly powerful processors generate intense heat that can limit performance and shorten equipment life.

Diamond could potentially carry heat away from these processors more effectively than conventional materials, allowing future chips to run at higher power without overheating.

Martin Roscheisen, the firm’s chief executive, said: “This is one of those milestones that once seemed almost impossible.”

He added: “Hundreds of DF engineers, scientists, and technicians contributed to us getting here. It is the accumulated result of countless experiments, failures, inventions, rebuilt machines, and insights over more than a decade.”

Diamonds are exceptionally good at conducting heat, making them potentially valuable for keeping electronics cool. However, scientists have struggled to grow individual crystals large enough for the manufacturing processes used by the semiconductor industry.

Diamond Foundry’s new creation is roughly the size of a standard eight-inch silicon wafer, the thin circular material used to manufacture thousands of electronic components.

Crucially, the diamond is a single continuous crystal, rather than smaller pieces joined together, making it more suitable for developing advanced electronic components.

The breakthrough also has major implications for Europe, where Diamond Foundry is developing a semiconductor manufacturing operation in Spain.

The project, backed by the Spanish government, involves planned investment totalling €2.35 billion by 2029, including €752 million from Spain’s state-owned technology investment body.

Diamond Foundry is developing synthetic diamond production in Trujillo, in western Spain, alongside a new facility in Zaragoza that will prepare diamond wafers for semiconductor manufacturing.

The investment forms part of efforts to strengthen Europe’s chip industry and reduce its reliance on overseas suppliers for advanced technology.

The company’s latest achievement was announced alongside a presentation by Roscheisen at the CarbonSemi 2026 conference in Ningbo, China.

He credited researchers Stefan Gsell and Martin Fischer, who began working on the challenge of growing larger single-crystal diamonds 25 years ago.

“Stefan and Martin pursued this goal for 25 years,” Roscheisen added. “There are very few examples in technology of someone sticking to a really hard scientific challenge with that level of perseverance.”

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_{Main image: Diamond Foundry’s newly grown 200mm single-crystal diamond, shown in its unpolished state, represents the culmination of 25 years of research into producing diamonds large enough for semiconductor manufacturing. The eight-inch crystal could eventually help computer chips dissipate heat more efficiently, potentially improving the performance and reliability of AI processors. Credit: Diamond Foundry}