Theses›Datacentre & AI compute›GaN-on-si substrates

GaN-on-si substrates

Merchant GaN-on-silicon power epitaxy leaks to the device makers who grow their own; only vertical GaN and defence GaN-on-SiC keep a door open.

  • Bear
  • Shut
  • $2.5B by 2035

The callThe bear case is more likely for a merchant supplier: device makers grow their own epitaxy because it is their costliest, most differentiating step, so the layer stays captive. The market still grows from $256M to about $2.5B by 2035 on datacentre GaN, mostly inside captive lines.

D1D2R1R2R3C1foragainst D1D2R1R2R3C1foragainst
Fig. 1The balance. Drivers and catalysts against restraints, each block sized by its weight; catalysts hang dashed because they have not happened yet, sized by their odds. It tips toward the restraints.
  1. D1AI datacentres move to 800V DC and EVs and grid need 1200V+; silicon is too slow and lossy, silicon carbide substrates are expensive.
  2. D2Lateral GaN-on-silicon tops out around 650V because of crystal mismatch defects; a low-defect vertical substrate would cover chargers through traction inverters.
  3. R1Epitaxy is the device makers' costliest and most differentiating step, so they grow it themselves and merchant suppliers get squeezed.
  4. R2Profit goes to Aixtron (41-42% gross margin, over 60% share) and foundries like GlobalFoundries; the merchant remainder is $0.2-0.5B by 2030.
  5. R3Bulk GaN is still a small, sub-6-inch market, and the best exit, Transphorm to Renesas, was $339M.
  6. C1First commercial datacentre power-GaN rollouts, with GlobalFoundries making GaN-on-silicon for Navitas and onsemi; most volume goes captive.2027
Rests onthe beliefs underneath
Supported by · confidence
What would prove itdated tests, open and resolved
202720282029today123456predictionswatch 202720282029today123456predictionswatch
Fig. 2Each ring is a dated test: dashed while open, struck through when overdue, ticked or crossed once resolved.
  1. 1>=3 of the top-7 power-GaN makers run captive GaN-on-Si epi and zero name a merchant house as primary supplier by end-2027.Dec 2027 · open
  2. 2Bulk/native GaN substrate stays a <$0.8B market and <6-inch through 2027.Dec 2027 · open
  3. 3At least 3 of the top 7 power-GaN makers growing captive epi with none naming a merchant supplier.Dec 2027 · open
  4. 4Bulk GaN still under $0.8B and under 6-inch; a vertical or bulk GaN design-in with a device maker or GlobalFoundries would reopen it.Dec 2027 · open
  5. 5No independent EU GaN-on-Si POWER epi supplier reaches >=EUR20M Series A+ (or a >5x exit) by end-2028; the merchant power-epi layer leaks to captive IDMs.Dec 2028 · open
  6. 6No EU merchant GaN-on-silicon power-epi company raising a €20M+ Series A.Dec 2028 · open
Expressionslisted, private, technologies
  • AIXA.DEAixtron
    • full
  • IFX.DEInfineon
    • cheap
     Auto power + microcontroller + SiC.
  • IQE.LIQE plc
    • full
     Epi-wafer leader for VCSELs + photonic lasers.
  • NVTSNavitas Semiconductor
    • speculative
     GaN + SiC for AI power supplies — datacenter PSU efficiency.
  • POWIPower Integrations
    • full
  • SOI.PASoitec
    • expensive
  • 9432.TNTT Advanced Technology (NTT-AT)
    • not screened
     Sells GaN-on-Si and GaN-on-SiC epitaxial wafers to device makers and researchers.
  • 5714.TDOWA Electronics Materials
    • not screened
     Sells GaN-on-Si epitaxial wafers for power and RF devices.
Private · 3 private companies; none in continental Europe.

Vertical Semiconductor · Innoscience · Qromis

2 more private companies tracked, not shown

Technologies
Who has already bet on itprivate rounds, from public sources

$485M raised by 3 companies, $194M of it in the last three years. Wave building: Money is arriving: recent rounds and tier-1 funds are in, but no runaway leader yet.

Backed by a top-tier venture firm: Vertical Semiconductor. Backed by a strategic investor: Innoscience.

  • $474MInnoscience
    • Founded 2015
     IPO (HKEX 2577), Dec 2024 $180M (STMicroelectronics, Jiangsu SOE Mixed Ownership Reform Fund, Dongfang Innovation Capital) · Series D, 2022 $474M (TI-Capital, ADDOR Capital, Haitong Innovation)
  • $11MVertical Semiconductor
    • Founded 2024
     Seed, Oct 2025 $11M (Playground Global, JIMCO)
  • ·Qromis
    • Founded 2015
     Venture round, 2020 (SPARX Group (Mirai Creation Fund II))