In this study change of surface properties of materials by ion beams treatments and/or DLC (Diamond like carbon) coatings deposition by direct linear ion beam are presented. DLC coatings received extensive interest due to the outstanding mechanical, optical and electrical properties. We demonstrated that various properties have been influenced by the selection of gas mixture and treatment/deposition parameters. Functional properties may be also controlled by doping DLC with a number of elements, some of them forming compounds in the deposited coatings. Results of surface treatment, DLC, and doped DLC coatings deposition on metals, steel, and plastic substrates are presented. Using specially selected gas mixtures precursors and temperature control by independent heater, it was possible to affect in a positive direction the coatings adhesion with ferrous substrates, to influence internal stresses and wear resistance. Influence on wear resistance and performance durability of cutting tools was extensively illustrated by Si and SiO_x doping during deposition. Doped DLC coatings exhibited reduction of the internal  stress, friction coefficient, have shown considerably better adhesion with iron and stainless steels. Hydrophobicity and surface energy of ion beam treated or coated  materials was evaluated by measuring water contact angle, and surface conductivity was measured using a specially designed probe. increase of hydrophobicity was obvious for SiO_x doped DLC coatings, and drastic change of surface conductivity has been shown. Surface morphology, composition, and chemical structure of the coatings on various substrates were investigated using SEM/EDS, XPS, SIMS, and Raman spectroscopy, to explain the changes in functional properties and performance.