Strange hardness characteristic of hydrogenated diamond-like carbon thin film by plasma enhanced chemical vapor deposition process

By creating nanostructures and controlling the hydrogen content and sp(3)/sp(2) bonding ratio, we report the formation of very hard (35.8 GPa) hydrogenated diamond-like carbon film at a self-bias of -100V using simple radio frequency-plasma enhanced chemical vapor deposition process. When the self-bias is varied and modifications such as incorporation of nitrogen and Ag interlayer are executed, the mechanical properties of such films, however, got altered that are correlated well with the structural changes investigated using various spectroscopic and microscopic techniques. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4775372]