Extended service life of graphite and C/C components
The coating improves product quality and increases process efficiency, thus reducing overall operating costs for our custmers. This coating extends the service life of graphite components and achieves the high-purity surface structures required in processing semiconductor materials.
Wide range of applications for SiC-coated graphite products
SiC-coated graphite products can be used in numerous applications within the value chain of the semiconductor industry:
We supply SiC-coated products made from high-strength isostatic graphite and carbon fiber-reinforced carbon. These include components for fluidized-bed reactors and STC-TCS converters, as well as reflectors for CZ units and wafer carriers for PECVD, Si epitaxy, and MOCVD units.
Material data of SIGRAFINE SiC Coating
| Typical properties | Units | Values | Analysis technique |
|---|---|---|---|
| Structure | beta (cubic) 3C polytype | XRD | |
| Orientation | Fraction (%) | 111 preferred | XRD |
| Bulk density | g/cm³ | 3.2 | XRD |
| Stoichiometry | 1:1 Sl/C | XPS | |
| Hardness | GPa | 40 | Nanoindentation |
| Fracture toughness | MPa m1/2 | 3.0 | Vickers Identer |
| Thermal expansion 100–600 °C (212–1112 °F) | 10-6K-1 | 4.3 | Dilatometer |
| E-modulus | GPa | 435 | Nanoindentation |
| Typical film thickness | µm | 100 | Beta backscatter |
| Surface roughness | µm | 2,5 | Profilometer |
Purity data of SIGRAFINE SiC Coating (Glow Discharge Mass Spectroscopy)
| Element | ppm | Element | ppm |
|---|---|---|---|
| Sodium | < 0,05 | Copper | < 0,01 |
| Magnesium | < 0,01 | Zinc | < 0,05 |
| Aluminum | < 0,04 | Gallium | < 0,05 |
| Phosphorus | < 0,01 | Germanium | < 0,05 |
| Sulfur | < 0,04 | Arsenic | < 0,005 |
| Potassium | < 0,05 | Indium | < 0,01 |
| Calcium | < 0,05 | Tin | < 0,01 |
| Titanium | < 0,005 | Antimony | < 0,01 |
| Vanadium | < 0,001 | Tungsten | < 0,01 |
| Chromium | < 0,05 | Tellurium | < 0,01 |
| Manganese | < 0,005 | Lead | < 0,01 |
| Iron | < 0,01 | Bismuth | < 0,01 |
| Nickel | < 0,005 |
SiC coating process
Silicon carbide is deposited as thin layers on carbon fiber-reinforced carbon by CVD (chemical vapor deposition). Deposition takes typically place at temperatures of 1,200-1,300 °C. The thermal expansion behavior of the substrate material should be adapted to the SiC coating to minimize thermal stresses.
