Carbon behavior on tungsten surface after carbon and hydrogen mixed beam irradiation

The carbon behavior near the surface layer of tungsten after hydrogen and carbon mixed ion beam irradiation was investigated with XPS. Depth profiles of atomic components near the surface layer depended on the concentration of carbon ions in the beam of 0.1% or 0.8% and beam fluence from 3 x 10(22)/m(2) to 3 x 10(24)/m(2). Carbon concentration at the local peak increased with increasing beam fluence. Comparison of the experimental results with the simulation results with EDDY code was performed. At the temperature of 653 K, the simulation results qualitatively corresponded to the experimental results except near the top surface. In the simulation at high temperatures, carbon profile drastically expanded into the bulk layer due to thermal diffusion. But in the experiment, such expansion of the carbon distribution with the temperature was not observed for temperature up to 913 K. (C) 2004 Elsevier B.V. All rights reserved.