GaN-on-SiC MOCVD Fab Presets
Load calibrated 150mm/200mm MOCVD reactor configurations, defense radar, and 5G MIMO benchmarks:
MOCVD Reactors, Precursors, Pricing & CAPEX
GaN-on-SiC MOCVD Heteroepitaxy Process Flowsheet
| Process Parameter | Output / Metric |
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| Revenue / Cost Line | Annual ($M/yr) |
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20-Year NPV & IRR Sensitivity: Epitaxy Yield vs. Epi-Wafer ASP
20-Year Discounted Cash Flow (DCF) Pro-Forma Schedule
10-Year Straight-Line Depreciation | 21% Tax | 1.5%/yr ASP Erosion| Year | Prime Wafers | RF Dice | Revenue ($M) | OPEX ($M) | EBITDA ($M) | Taxes ($M) | Free Cash Flow ($M) | Discounted FCF ($M) | Cumulative FCF ($M) |
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Governing GaN Heteroepitaxy & 2DEG Physics Relations
1. MOCVD Synthesis Reaction
High-temperature vapor phase reaction:
Ga(CH3)3 + NH3 → GaN + 3CH4↑
Carried out at 1,000–1,100°C in H2/N2 at 100–200 mbar with V/III > 1,000.
2. 2DEG Sheet Carrier Density
Polarization charge divergence at AlGaN/GaN:
ns = |Ptot(AlGaN) − Ptot(GaN)| / q
Total polarization Ptot = PSP + PPE yields ns ∼ 1×1013 cm−2 without impurity doping.
3. Sheet Resistance
Product of carrier density and electron mobility:
Rsh = 1 / (q × ns × μ)
For μ ∼ 2,000 cm2/V·s, Rsh reaches an ultra-low 310–350 Ω/sq for low conduction loss.
GaN-on-SiC Epitaxy & RF Power Mastery Quiz
Frequently Asked Questions (FAQ)
Semi-insulating 4H-SiC features a high thermal conductivity of ~3.8 to 4.9 W/cm·K (roughly three times silicon and ten times sapphire) and a close lattice match (~3.4% mismatch vs ~17% on silicon). High-power RF amplifiers in 5G base stations and AESA radar dissipate extreme power densities (>5 to 10 W/mm), requiring the superior thermal dissipation of SiC to avoid junction thermal runaway.
Wurtzite III-nitride crystals lack inversion symmetry along the c-axis, producing large spontaneous polarization. When pseudomorphic AlGaN is grown on GaN, tensile strain induces additional piezoelectric polarization. The resulting gradient in polarization charges at the heterointerface pulls electrons into a triangular quantum well, forming a 2DEG with sheet carrier density ns ~ 1e13 cm−2 and electron mobility exceeding 2,000 cm²/V·s.
A thin (20–40 nm) high-temperature AlN nucleation layer wets the SiC surface to establish atomic epitaxy and prevent melt-back etching. Subsequent iron (Fe) or carbon (C) deep-level acceptor doping of the GaN buffer traps residual donor electrons, preventing buffer leakage currents and ensuring sharp pinch-off at high drain operating voltages (50V to 150V).
The primary metalorganic precursors are Trimethylgallium (TMGa) and Trimethylaluminum (TMAl), delivered by high-purity hydrogen (H₂) or nitrogen (N₂) carrier gases into the reactor chamber at 1,000 to 1,100°C. Ultra-pure 7N ammonia (NH₃) supplies active nitrogen at high V/III ratios (>1,000) to suppress nitrogen vacancy defects.
The model simulates annual MOCVD runs from reactor count, platter capacity, and cycle frequency, factors in substrate costs, TMGa/TMAl and NH₃ precursor consumption, electricity, and cleanroom metrology QA, then projects a 20-year DCF with 10-year depreciation, 21% tax, 1.5% annual ASP erosion, and computes NPV, IRR, and payback.