Chemical Vapour Deposition is a coating process in which solid substances are deposited from gaseous compounds on a surface by means of chemical reaction. auf einer Oberfläche aus gasförmigen Verbindungen feste Substanzen abgeschieden werden. To trigger the chemical reaction, the substrate must be heated to high temperatures. Not every substrate has the thermal stability required. Heating of the substrate can be reduced or even avoided by having a plasma excite the chemical reaction above the surface of the substrate. This process is called PECVD (Plasma Enhanced Chemical Vapour Deposition) or also PACVD (Plasma Activated CVD). Plasma CVD processes are mainly used to produce amorphous carbon and silicon coats as well as titanium nitride, titanium carbide, or silicon nitride coats.