Modeling for the Diamond-Like Carbon Film Synthesis by Plasma Based Ion Implantation

Dynamic Monte Carlo simulations with the binary collision approximation have been applied to the synthesis of hydrogenated amorphous carbon ( a -C:H) films by plasma based ion implantation (PBII). We take as representative carbon carriers energetic CH 3 + ions and CH 3 radicals. The direct chemical incorporation of the radicals, like CH 3 reacting with a diamond surface, is too low for the deposition of DLC films, so that the other reaction mechanisms should be responsible. We assumed (a) complete dissociation of CH 3 + ions into one C atom and three H atoms with identical velocities upon bombarding the surface, (b) a unity and only one mono-layer sticking of CH 3 radicals on the surface, (c) incorporation (stitching) of H and C atoms under the surface induced by binary collisions with energetic CH 3 + ions, (d) release of H atoms by the dissociation of CH 3 radicals on the surface, and (e) release of a part of displaced H atom after the subsequent collision cascade. We also assumed only the stitched carbon atoms form sp 3 states and all other carbon atoms form sp 2 states. The effect of the target voltage on the ion dose was also included. The effects of ion/neutral arrival ratio and ion energy on the growth rate, the mixing layer thickness, the hydrogen content, and the sp 3 /sp 2 ratio in the deposited film are presented.