4inch SiC Epitaxial Wafer 4H-N Diameter 100mm Thickness 350μm Prime Grade
As a core material for silicon carbide (SiC) power device manufacturing, the 4-inch SiC epitaxial wafer is based on a 4H-N-type SiC wafer, grown using chemical vapor deposition (CVD) to produce a high-uniformity, low-defect-density single-crystal thin film. Its technical advantages include:
· Crystal Structure: (0001) silicon-face orientation with a 4° offcut to optimize lattice matching and reduce micropipe/stacking fault defects.
· Electrical Performance: N-type doping concentration precisely controlled between 2×10¹⁴–2×10¹⁹ cm⁻³ (±14% tolerance), achieving resistivity adjustable from 0.015–0.15 Ω·cm via in-situ doping technology.
· Defect Control: Surface defect density <25 cm⁻² (TSD/TED), triangular defect density <0.5 cm⁻², ensured by magnetic-field-assisted growth and real-time monitoring.
Leveraging domestically developed CVD equipment clusters, ZMSH achieves full-process control from wafer processing to epitaxial growth, supporting rapid small-batch trials (minimum 50 wafers) and customized solutions for applications in new energy vehicles, photovoltaic inverters, and 5G base stations.
Key parameters for 4inch SiC epitaxial wafers
| Parameter | Specification |
| Diameter | 100 mm (±0.1 mm) |
| Thickness | 10–35 μm (low voltage) / 50–100 μm (HV) |
| Doping Concentration (N) | 2×10¹⁴–2×10¹⁹ cm⁻³ |
| Surface Defect Density | <25 cm⁻² (TSD/TED) |
| Resistivity | 0.015–0.15 Ω·cm (adjustable) |
| Edge Exclusion | 3 mm |
Core characteristics & technical breakthroughs of 4inch SiC epitaxial wafers
1. Material Performance
- Thermal Conductivity: >350 W/m·K, ensuring stable operation at >200°C, 3× higher than silicon.
- Breakdown Field Strength: >3 MV/cm, enabling 10kV+ high-voltage devices with optimized thickness (10–100 μm).
- Carrier Mobility: Electron mobility >900 cm²/(V·s), enhanced by gradient doping for faster switching.
2. Process Advantages
- Thickness Uniformity: <3% (9-point test) via dual-temperature zone reactors, supporting 5–100 μm thickness control.
- Surface Quality: Ra <0.5 nm (AFM), optimized by hydrogen etching and chemical mechanical polishing (CMP).
- Defect Density: Micropipe density <1 cm⁻², minimized through reverse-bias annealing.
3. Customization Capabilities
- Crystal Orientation: Supports (0001) silicon-face, (11-20) carbon-face, and quasi-homoepitaxial growth for trench MOSFETs and JBS diodes.
- Packaging Compatibility: Offers double-sided polishing (Ra <0.5 nm) and wafer-level packaging (WLP) for TO-247/DFN.
Application scenarios & technical value of 4inch SiC epitaxial wafers
1. New Energy Vehicles
- Main Drive Inverters: 1200V epitaxial wafers for SiC MOSFET modules, improving system efficiency to 98% and reducing EV range loss by 10–15%.
- Fast Charging: 600V wafers enabling 800V platforms for 30-minute 80% charging (e.g., Tesla, NIO).
2. Industrial & Energy
- Solar Inverters: 1700V wafers for DC-AC conversion, boosting efficiency to 99% and lowering LCOE by 5–8%.
- Smart Grids: 10kV wafers for solid-state transformers (SST), reducing transmission losses to <0.5%.
3. Optoelectronics & Sensing
- UV Detectors: Utilizing 3.2 eV bandgap for 200–280 nm detection in flame monitoring and biochemical threat detection.
- GaN-on-SiC RF Devices: HEMTs on 4-inch wafers for 5G base stations, achieving 70% PA efficiency.
4. Railway & Aerospace
- Traction Inverters: High-temperature wafers (-55°C–200°C) for IGBT modules in bullet trains (AEC-Q101 certified).
- Satellite Power: Radiation-hardened wafers (>100 krad(Si)) for deep-space DC-DC converters.
ZMSH's service of SiC wafer
1. Core Competencies
· Full-Size Coverage: 2–12-inch SiC substrates/epitaxial wafers, including 4H/6H-N, HPSI, SEMI, and 3C-N polytypes.
· Custom Fabrication: Custom cutting (through-holes, sectors), double-side polishing, and WLP.
· End-to-End Solutions: CVD epitaxy, ion implantation, annealing, and device validation.
2. Production Capacity
· 6-inch Wafers: 360,000 annual capacity; 8-inch R&D line operational.
· Certifications: IATF 16949-certified, >95% yield for automotive-grade products.
· Cost Leadership: 75% domestic CVD equipment, 25% lower costs vs. international competitors.
The following is the recommended 3C-N type for SiC substrates:
FAQ of 4inch SiC epitaxial wafers
