Comparison of carbon deposition on tungsten between molecular dynamics and dynamic Monte Carlo simulation

To investigate the low-temperature plasma wall interactions in fusion devices, e.g., ITER, we have developed a molecular dynamics (MD) simulation code. The calculated results are compared with the dynamic Monte Carlo (MC) simulation. The W surface is bombarded with C atoms at the temperature of 10 eV–1keV. During the plasma exposure with low temperature, a thick C layer is formed on the W surface. At high plasma temperature W surface is eroded and the W-C mixed layer is formed. These results are consistent with the calculated ones with the dynamic MC code, EDDY [K. Ohya, Phys. Scr. T124, (2006) 70.]. Inhomogeneous deposition of C is calculated, which indicates that atomic scale roughness is important for the development of C deposition and material mixing.