Silicon Carbide (SiC) Based Vacuum Chuck for High-Temperature & Plasma Environments
St.Cera’s SiC-based ceramic chuck is manufactured from high-purity silicon carbide (batch S1111, SiC 99.72%, free Si 0.05%). It delivers measured flexural strength of 449 MPa, fracture toughness of 3.12 MPa·m¹/², and elastic modulus of 457 GPa. The material’s typical thermal conductivity (120–150 W/m·K) and low thermal expansion (4.0–4.5×10⁻⁶/℃) enable rapid temperature ramping and minimal wafer warpage during thermal cycling. The chuck can be configured as a porous vacuum chuck (uniform gas flow) or a grooved standard chuck. With a maximum use temperature of 1600–1700°C (no load) and exceptional plasma erosion resistance, this chuck is ideal for high-temperature wafer processing (annealing, RTP) and aggressive etch chambers where alumina chucks degrade.
Specifications (based on supplied SiC S1111 test report & typical values):
| Property | Value |
| Material | SiC (99.72% SiC, 0.05% Free Si) |
| Density | 3.10–3.15 g/cm³ |
| Water Absorption | 0% |
| Flexural Strength | 449 MPa |
| Fracture Toughness | 3.12 MPa·m¹/² |
| Elastic Modulus | 457 GPa |
| Vickers Hardness | 25–28 GPa |
| Thermal Conductivity | 120–150 W/m·K |
| CTE (25–1000°C) | 4.0–4.5×10⁻⁶/℃ |
| Max Use Temp (no load) | 1600–1700°C |
| Flatness (over 300mm) | ≤5 μm |
| Surface Finish | Ra ≤0.4 μm (lapped) |
Applications:
● High-temperature chucking (annealing, RTP, epitaxial growth)
● Plasma etch chuck with high fluorine resistance
● Thin wafer handling with uniform heating/cooling
● Porous chuck for non-contact wafer support
Manufacturing:
SiC sintering → precision grinding of flatness and surface profile → optional porous structure formation (for vacuum chuck) → lapping → ultrasonic cleaning. Each chuck is 100% inspected for flatness (laser interferometer) and vacuum uniformity (flow test).
Quality Control:
● CMM dimensional check (diameter, thickness, hole positions)
● Flatness measurement per ASTM
● Helium leak test (for vacuum chucks)
● Flexural strength verification per batch (ref. test report)
Advantages over Alumina Chucks:
● Higher thermal conductivity (120–150 vs 32 W/m·K for alumina) – 4× faster heat transfer
● Lower CTE (4.0 vs 7.2×10⁻⁶/℃) – reduces wafer thermal stress
● Superior plasma resistance – 10× longer lifetime in fluorine etch
● Higher maximum use temperature (1600°C vs 800°C for alumina)
Customization:
● Porous or grooved surface
● Diameter 100–450 mm, round or square
● Edge sealing ring or zone vacuum partitions
● Metal backing option for high-rigidity mounting
All mechanical data above comes from the supplied test report (batch S1111). Thermal and hardness values are typical for this SiC grade. Porous SiC chucks require additional processing; please inquire for specific porosity and pore size availability.
