AVS 54th International Symposium | |
Advanced Surface Engineering | Monday Sessions |
Session SE-MoM |
Session: | Hard and Nanocomposite Coatings: Synthesis, Structure, and Properties |
Presenter: | S.V. Singh, Eindhoven University of Technology, The Netherlands |
Authors: | S.V. Singh, Eindhoven University of Technology, The Netherlands M.A. Creatore, Eindhoven University of Technology, The Netherlands R. Groenen, NV Bekaert SA, Belgium K. van Hege, NV Bekaert SA, Belgium M.C.M. van de Sanden, Eindhoven University of Technology, The Netherlands |
Correspondent: | Click to Email |
A novel form of diamond-like hydrogenated carbon deposited utilizing the expanding thermal remote Ar/C2H2 plasma is reported. The plasma is generated in a cascaded arc at subatmospheric pressure in argon. The discharge expands into a low pressure (remote) chamber where acetylene is introduced downstream by means of an injection ring. The downstream plasma is characterised by a low electron temperature which leads to ion driven chemistry and negligible physical effect like ion bombardment (< 2 eV) on the substrate. Distinct from previous works, relatively low argon to acetylene gas flow ratio has been used in this study. Infrared absorption shows a reduced concentration of CH stretching and in addition, it is also evident that the endgroups (sp2 - CH2 and sp3 - CH3) are absent in the films. Theses films posses relatively low optical band gap and hydrogen content, high refractive index and a nanohardness exceeding 16 GPa. Further characterizations by means of Raman spectroscopy, spectroscopic ellipsometry (SE) and Rutherford back scattering (RBS) indicate that the films are well cross-linked graphite like hydrogenated amorphous carbon. The film properties will be interpreted in view of the specific plasma chemistry taking place in the expanding thermal plasma.