Growth of nanocrystalline diamond films by biased enhanced microwave plasma chemical vapor deposition: A different regime of growth

Hard and smooth nanocrystalline diamond films are grown on mirror polished silicon substrates by biased enhanced growth (BEG) in microwave plasma chemical vapor deposition at lower temperatures. Hardness of the films varies with deposition condition and can be defined by the relative concentration of nanocrystalline diamond in the films, as measured by the Raman intensity ratio of the feature near 1150 cm(-1) to the intensity of graphitic G band. The hardness of the films approaches the hardness of diamond at conditions giving maximum concentration of nanocrystalline diamond while still having a low amount of stress (1-2 GPa). A different regime of growth appears to exist in the films deposited by the BEG process that may, however, be a combination of surface and subsurface processes. (C) 2000 American Institute of Physics. [S0003-6951(00)05051-8].