Growth of diamond-like carbon films using low energy ion beam sputter - bombardment deposition with Ar ions

An alternative to a widely used ion assisted deposition method has been developed where a single beam of low energy Ar ions is used to simultaneously sputter a graphite target and to bombard a growing film. By placing the substrate at low incident angles to the axis of the ion beam and therefore subjecting the growing film to the additional ion energy we aimed to promote the formation of sp(3) bonding. Sp(2) rich amorphous carbon (a-C) and diamond-like carbon (DLC) films with significant fractions of sp(3) bonding were formed by sputtering from a Kaufmann-type ion source. Experimental results revealed that when the substrate was placed at grazing angles to the incoming ions no DLC, but only polymeric a-C films were produced as a result of a secondary resputtering process. For DLC synthesis the optimal angles of the target and the substrate to the ion flux were found to be 30 degrees and 0 degrees respectively and the ion energies of 0.8-1.0 keV.