Structural and nano-mechanical properties of nanostructured diamond-like carbon thin films

The effect of self bias on structural and nano-mechanical properties of nanostructured diamond-like carbon (ns-DLC) thin films is explored. These films are grown at different negative self biases ranging from −100 V to −200 V using radio frequency (13.56 MHz) plasma enhanced chemical vapor deposition technique. The generation of nanostructured morphology at room temperature in these films is confirmed by scanning electron microscopy, whereas change in microstructure produced by varying the self biases is confirmed by Raman analysis. These ns-DLC films exhibit very high hardness, which varied from 16 GPa to 31 GPa. With the help of load versus displacement curves, various other important nano-mechanical parameters such as elastic modulus, elastic recovery etc are also estimated. The nano-mechanical properties are further correlated with the Raman and SEM analyses. Owing to their versatile nano-mechanical properties, these ns-DLC films may find application as hard and protective coatings.