Direct verification of the ion-neutral synergism during hydrocarbon film growth

Elementary ion-induced surface processes during plasma deposition of amorphous hydrogenated carbon films are studied in a particle-beam experiment employing sources for noble gas ions and CH3 radicals. Two processes govern film formation: (1) Ion-assisted film growth: Incident ions displace surface-bonded atoms and create dangling bonds which then serve as chemisorption sites for incident radicals, and (2) Ion-induced hydrogen release: Incident ions alter the film composition by preferential removal of bonded hydrogen in the subsurface of the growing film. It is shown that both elementary processes are in quantitative agreement with displacement yields as calculated by computer simulations. (C) 2003 American Institute of Physics.