Characterization and erosion of metal-containing carbon films

The annealing of magnetron-sputtered carbon films doped with up to 8.5 at.% W, Ti, V, and Zr prior to the erosion experiments led to the formation of carbide cyrstallites of several nm. The total erosion yield by 30 and 200 eV D(-1), impacting as D(3)(+) projectiles, at 300 K and similar to 750 K was determined from film thickness changes measured by ion beam analysis. Doping with W, Ti, V, and Zr always reduces the total erosion yield by a factor of up to 20 compared to a pure C film. The temperature dependency of the metal erosion was observed. The methane production yield was studied by mass spectrometry. The CD(4) production yield decreases less than the total yield or even increases. This implies that the distribution of the chemically eroded species is changed by the dopants. It can be speculated that the re-deposition of carbon is reduced by doping.