Deposition of hydrogenated carbon layers from CH 3+ ion beams

Abstract

Carbon deposition and hydrogen codeposition is investigated as function of ion energy, fluence and target temperature at normal incidence by bombardment of hydrocarbon molecules onto Si and graphite. An amorphous hydrogen/carbon (a-C:H) layer is formed in a thickness range of 40 to 130 nm by CH 3 + bombardment up to a fluence of 3 × 10 18 / cm 2. The deposition process and the re-erosion phenomenon of the carbon film is also studied. The experimental results are compared with TRIDYN computer simulation and previous experimental results of carbon sputtering by atomic H + and C + beams in order to have a good understanding of the interaction between hydrocarbon molecular ions and the carbon-based wall in fusion devices.