Free-standing diamond films deposited by DC arc plasma jet on graphite substrates with a destroyable Ti interlayer

A destroyable Ti interlayer on graphite substrate was used for fabrication of crack-free free-standing diamond films by high-power DC Arc Plasma Jet. Ti interlayer was arc ion plated on the polycrystalline graphite substrate. The thickness, morphology and composite phase of the Ti interlayer were examined by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Titanium carbide (TiC) was detected in both sides of the interlayer, which played an important role with respect to reasonable adhesion and diamond nucleation. Semi-translucent and crack-free diamond films were obtained and characterized by SEM and Raman spectroscopy. It is shown that the diamond films so obtained have excellent Raman signature. The overall results suggest that plating Ti interlayer on graphite substrate is an effective way to obtain potentially crack-free free-standing diamond films.