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.