BCN coatings on polymer substrates by plasma CVD at low temperature

An overview is given of the plasma-assisted techniques for coating ceramics on polymer substrates at low temperature. Depositon of boron carbon nitride was carried out on polycarbonate substrates by a radio-frequency plasma-assisted chemical vapor deposition process using different metallo-organics as precursors. The films deposited were found to be stable and adherent under ambient conditions. The chemical compositon of the layers varied in a wide range. Nearly stoichiometric BCN layers, as well as films with a high carbon content, were obtained. The chemical bonding of boron, caron and nitrogen was analyzed by X-ray photoelectron spectroscopy. The deposited films have a high transparency (90 %) in the ultraviolet-visible region. The transmission depends on the layer thickness and on the precursor used. The coatings have a hardness of up to 1500 HK 0.005.