LOW-TEMPERATURE PLASMA-ASSISTED CHEMICAL-VAPOR-DEPOSITION OF AMORPHOUS-CARBON FILMS FOR BIOMEDICAL-POLYMERIC SUBSTRATES

Preliminary results have been obtained on the biocompatibility of amor phous carbon hydrogen (alpha C:H) coatings deposited on polystyrene. D eposition was carried out at low substrate temperatures using pulsed r .f. plasma-assisted chemical vapour deposition from a methane-hydrogen gas mixture. Cytotoxicity tests using a standard cell line indicate a high degree of biocompatibility. Specifically, alpha C:H is not toxic to cells, appears to increase cell attachment and affords normal cell growth rates. Wear and other tests have revealed no significant diffe rences between these alpha C:H coatings and those deposited on a stain less steel at a higher substrate temperature, except for a more pronou nced surface texture. However, position in the r.f. plasma was found t o be critical for the deposition of good, adherent low temperature coa tings.