Specialty Foundries (TFLN, GaN, SiC, photonic)

Physics / mechanism

Specialty foundries serve compound semiconductor and exotic-material processes that silicon CMOS fabs won’t run. TFLN (thin-film lithium niobate) delivers electro-optic bandwidths >100 GHz with sub-volt Vπ·L figures (~2 V·cm), enabling co-packaged optics and microwave photonics. GaN-on-SiC targets RF power density >10 W/mm at 10 GHz plus breakdown fields ~3.3 MV/cm for 5G/defense PA stacks. SiC (4H polytype) offers 650–1700 V device ratings with on-resistance one-tenth of silicon equivalents, dominating EV inverters. Photonic foundries (SiPh via GlobalFoundries, IMEC; InP via SMART/Fraunhofer) integrate passive + active layers with 200 mm wafer-scale yields now crossing 80% on standard PDKs.

Competitive landscape

GaN competes directly with GaAs at frequencies below ~6 GHz and with SiC MOSFET at medium-voltage power; SiC competes with GaN-on-Si above ~900 V. TFLN competes with silicon photonics (lower EO coefficient, higher Vπ) and InP (monolithic gain but expensive, small wafers).

Companies using

Connected ideas

Sources

Frontier (open questions)

• To be added.