Methods of production, structure, and properties of film materials based on the carbon-nitrogen system (survey)

About 50 papers devoted to producing and investigating the properties of ca rbon nitride films are critically reviewed If is shown that reasonable expe rimental confirmation of synthesis of the hypothetical beta-C3N4 does not y et exist. Carbon nitride films can be produced practically by all PVD and C VD methods. They may contain up to 50% nitrogen, have an amorphous structur e, and atoms in carbon nitride sp(2)-bonded. The microstructure of amorphou s CN films is mostly based on two types of clusters-cyanogen polymers and g raphite-like domains with carbon atoms partially substituted by nitrogen. T he relation between two microstructure types depends on the deposition cond itions and crucially influences the film properties The smaller the graphit e-like clusters size and the more chaotically they are oriented in the film the harder will be the plm The factor which influences most the type of fi lm microstructure and properties is the ion bombardment of the film during the deposition. The small friction coefficient, high elasticity, and relati vely high hardness of nitride carbon films may make them useful as protecti ve coatings of a storage medium in computers.