FORMATION OF THE SURFACE LAYER BY VACUUM DEPOSITION OF COBALT AND MOLYBDENUM ON GRAPHITE
Analysis of chemical bonds, element composition and depth distribution of component in coating formed by self ion-assisted deposition of metal (Mo, Со) onto graphite using a method in which the metal deposition was accompanied by bombardment Mo+ or Со+ ions is reported. Analysis was carried out using Rutherford back scattering and X-ray photoelectric spectroscopy methods. Elemental analysis of the coatings on graphite shows a high content of carbon, oxygen and of the silicon as a result of counter-diffusion from the substrate into the coating. The findings have allowed to determine the presence of metal Mo and Mo oxide fractions. Thickness of the coatings are increases with the decrease of the accelerating voltage for assisting Со+, Мо+ ions from 20 to 7 kV and depends on the relationship of the flux density of ions J to the flux density of deposited atoms Ja (Jt / Ja) and type deposited on graphite metal. It is established that the optimal ratio of Jt / Ja at which is reached the maximum thickness Co-coating is 0,01 and for Мо-coating - 0,18. The calculated average deposition rate of the coating was 0,3-0,9 nm/min for the Co - graphite system and 0,2-0,4 nm/min for the Mo - graphite system.