HexSeed raises over £600k for diamond on GaN tech
UK start-up HexSeed Technology has raised over £600k in early funding to demonstrate a process for coating diamond on commercial GaN power devices, and progress toward pilot customer engagements, with data centre power conversion hardware as the initial target market.
HexSeed was founded in late 2025 by Mark Tandy (CEO, Oxford MBA), Leonardo Santoni (CTO, PhD in chemistry from UCL) and Michael Glerum (COO, PhD in Engineering from Cambridge). Together with researchers from the University of Bristol, the firm is developing a low-temperature microwave plasma process that grows diamond coatings directly onto finished GaN devices, pulling heat away from the active regions so they run harder, last longer, and use less energy.
The cumulative investment led by Carbon13, with participation from Net Zero Technology Centre and Vento Ventures unlocks a Partnership Grant from Innovate UK, awarded on a provisional basis earlier this year.
“Data centres are on track to consume a significant share of UK grid capacity within the decade, and a large proportion of that energy is lost as heat in power conversion. This funding will allow us to take our low-temperature diamond coating technology which we are developing from laboratory demonstration to working GaN devices.” said Mark Tandy
