Typical CVD/CVI Coatings:-
Coating Material |
Process Gases |
Typical Deposition Temperatures (degC) |
Silicon Carbide | CH3SiCl3 |
1300 |
Boron Nitride | BCl3-NH3 |
1800 |
Carbon (graphite) | CH4-H2 |
2200 |
Titanium Carbide | TiCl4-H2 |
800 |
Titanium Nitride | TiCl4-N2 |
900 |
Silicon Nitride | SiCl4-N2-NH3 |
1300 |
Aluminium Nitride | AlCl3-NH3 |
800 |
The PSI CVD/CVI systems are designed and tested to international standards. Constructed from stainless steel the vacuum-pressure vessel encases either a vertically or horizontally orientated corrosion-resistant furnace. Typically manufactured in graphite the retort facilitates hot zones of 600mm diameter x 900mm long down to research-scale systems of 150mm diameter x 460mm. Furnace temperatures of 1300degC are achieved as standard with a high temperature alternative to 2200degC. Specialist, chemically-resistant vacuum facilities are essential as the gas scrubbing system for compliance with local disposal regulations.
With some CVI processing taking days to complete, a fully-automated PLC-based control system and data-logging is essential. Computer-control is available for remote operation and full process data-logging for QC/QA requirements. For client satisfaction purposes, it is PSI’s policy to define the eventual equipment specification only after technical discussion with the client and our own consultants.