PACVD process

The technology

In the plasma-activated CVD process (PACVD, PECVD), a plasma supports the precipitation of layers from the gas phase. Precursors (in the form of gases or vapours) containing the elements of the layer material are used. At Fraunhofer IST this method is used primarily for the precipitation of modified diamond-like carbon films (a-C:H:X, X stands for the additional elements that are introduced, for instance Si, O, F). Compounds such as TMS or HMDSO are used as precursors. Hard material films like TiN or TiCN can also be produced with PACVD processes.

Advantages

Modified a-C:H:X films are used in particular to specifically alter the wetting behaviour. These a-C:H:X films are electrically insulating and can therefore be produced only with PACVD. Another key benefit of PACVD processes is that much lower temperatures can be used in contrast to pure CVD processes (a-C:H:X: < 200 °C). Fraunhofer IST operates several PACVD systems, including one with typical industrial dimensions (> 1 m³). Typical coating rates today are in the range of 1 µm/h.