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.