A concept of basic relations for ion assisted film growth conditions is presented and applied to establish a relationship between the industrial requirements of coating techniques and processing. Additionally, deposition parameter ranges can be estimated from these relations which is applied to the deposition of hard carbon coatings from free atoms and ions. Thereby, the formation of sp3 bondings, is considered to be a sensitive probe of film forming processes. The selection of cathodic arc technique for the deposition of hard carbon coatings is justified for the industrial requirements. Results of the deposition experiments are presented.