Diamond Foundry says it has grown first 200 mm single-crystal diamond

The crystal is shown as grown and unpolished, directly from the growth process, according to a press release from Diamond Foundry. The company stresses that it is neither an assembly of smaller diamond pieces nor a polycrystalline wafer, but a single crystal diamond at D200mm scale. 

Diamond combines the highest thermal conductivity of any material with mechanical strength and electrical insulation, but its use in electronics has been limited by how small the crystals can be made. For AI processors, which concentrate large amounts of power in small areas of silicon, Diamond Foundry says diamond could spread heat at the material level and open up new possibilities for chip design, power density and cooling.

According to the company, the result builds on 25 years of work by Stefan Gsell and Martin Fischer on scaling up single-crystal diamond, later carried forward by hundreds of engineers and scientists at Diamond Foundry. Reaching 200 mm required breakthroughs across crystal growth, growth chemistry, plasma physics, reactor architecture, thermal management, metrology, process control and automation.

"Stefan and Martin pursued this goal for 25 years," Roscheisen said. "There are very few examples in technology of someone sticking to a really hard scientific challenge with that level of perseverance. They kept going when the prevailing view was that single-crystal diamond simply could not be made at this scale. Today, the perseverance shows as the first-ever D200mm single-crystal diamond. And best of all, it makes D300mm predictable as well."

Diamond Foundry does not give data on the crystal’s thickness or quality, or say when diamond wafers of this size could be commercially available.