Abstract

Tetrahedral amorphous carbon (ta-C) films have been prepared with floating potential (no substrate bias voltage) on Si substrates by an off-plane double bend filtered vacuum cathodic arc (FCVA) system. The influences of arc current on mass density, chemical bonding and nanomechanical response have been studied for coatings. Based on X-ray reflectivity spectra, the maximum density of FCVA films is 3.27 g/cm(3). The hardness measurements performed as a function of indentation depth for 75-nm-thick films have a maximum hardness of 37.5 GPa and stress values up to 13 GPa. The sp(3) content in the ta-C films as determined by analysis of the C 1s core level spectra had a value of approximately 80% with standard deviation value 1.2% on 6-cm diameter Si waver. Therefore, these coatings have both structural and thickness uniformity, which can be used for large area coating applications (i.e. flat panel display units). (C) 2003 Elsevier B.V. All rights reserved.