Plasma‐enhanced deposition of diamond‐like carbon films on high temperature tolerant polymers

Abstract

AbstractThe feasibility of depositing carbon films with a diamond‐like structure on high temperature polymers, using established plasma‐enhanced chemical vapor deposition techniques, is explored. Potential uses for such a film will depend upon the adhesion of the film to the substrate, the properties of the deposited film, and the effect of the deposition process on the bulk properties of the polymer substrate.Amorphous carbon (diamond‐like carbon) coatings with thicknesses ranging from 2 to 18 μm were deposited on polyimide substrates at temperatures below 420°C. Extended exposure to the plasma processing conditions caused no visible damage but halved the room‐temperature tensile strength of the polymer films. Diamond‐like carbon, graphitic carbon, and a precursor to the diamond‐like carbon structure, attributed to an aromatic carbon ring structure, were observed. The optical transparency of the coated polymer film was attenuated uniformly across the spectral range, 2.5‐22 μm. Static oxidation and limited thermal cycling of the coated polymer produced no widespread delamination of the coating from the substrate: neither the deposited film nor the coated regions of the polymer showed any effect when oxidized at 370°C, for 450 h. © 1994 John Wiley & Sons, Inc.