HexSeed raises over £600,000 for AI chip cooling technology

HexSeed Technology has secured more than £600,000 in early-stage funding to expand its low-temperature diamond coating technology. The Scottish semiconductor materials startup aims to use the investment to prevent overheating in power semiconductors used in artificial intelligence infrastructure. The funding round was led by climate-tech venture builder Carbon13, with additional backing from the Net Zero Technology Centre and Italian venture capital firm Vento.

Founded in late 2025 by chief executive Mark Tandy, CTO Dr Leonardo Santoni, and COO Dr Michael Glerum, the company develops advanced thermal management materials. HexSeed operates a carbon capture and utilisation model that converts captured carbon dioxide into industrial-grade synthetic diamond films. In collaboration with researchers at the University of Bristol, the team is developing a low-temperature microwave plasma technique to grow these diamond coatings directly onto fabricated gallium nitride chips. This process is designed to dissipate heat away from active device regions, thereby extending chip lifespans and improving thermal efficiency.

Gallium nitride transistors are considered a potential successor to silicon-based chips due to their more efficient power conversion. HexSeed intends to support this industry transition with its thermal solutions. The startup plans to use the new capital to validate the coating process on commercial gallium nitride devices and launch pilot customer trials. The primary market target is data centre power conversion hardware, where significant energy is currently lost as heat. Mark Tandy noted that data centres are on track to consume a substantial share of UK grid capacity within the decade. He stated that the funding will enable the company to move its technology from laboratory demonstration to working devices.