Koolstoffilms

Koolstoffilms (Dutch for carbon films) are thin coatings composed primarily of carbon. They encompass a range of microstructures from amorphous carbon to graphitic carbon and diamond-like carbon (DLC). Depending on bonding and microstructure, carbon films can be insulating, semiconducting, or, in some cases, conductive, and they may be used as pure carbon layers or as composites with other elements.

Koolstoffilms are deposited on substrates by various processes. Common methods include chemical vapor deposition (CVD) and plasma-enhanced CVD, physical vapor deposition (PVD) such as sputtering or evaporation, and pyrolysis of hydrocarbon precursors. In solution-based approaches, polymer-derived carbon films are produced by coating and subsequent high-temperature carbonization. The choice of method influences film density, bonding (sp2 vs sp3 content), hydrogen incorporation, stress, and adhesion.

Key properties of koolstoffilms include chemical inertness, hardness (especially for diamond-like carbon), optical transparency in some spectral ranges, and a wide range of electrical conductivities. They can provide protective, wear-resistant, diffusion-barrier, or interfacial functions in devices, and they are used as electrode materials in energy storage and as functional layers in microelectronics and sensors.

Historically, carbon films have been used in electronics, for example as carbon film resistors where a carbon layer deposited on ceramic forms the resistive element. Research continues to tailor carbon films for specific mechanical, electrical, and optical requirements.

See also: graphitic carbon, diamond-like carbon, carbon nanotube films, graphene films.