Properties of laser fabricated nanostructured Cu/diamond-like carbon composite

Abstract

Copper/diamond-like carbon (DLC) was fabricated using pulsed laser deposition, and the effects of copper on the properties of DLC composites were studied. Experimental results showed that the presence of copper promoted surface evolution through the formation of nanoclusters, accentuated the formation of Si-C but graphitized the diamond bondings of DLC matrix. By considering the interaction of laser with copper/carbon composite target, the presence of copper may have increased the energy absorbed during laser deposition, as envisaged by Saha's equation. Thus, upon the impingement of ions on substrate during deposition, the carbon and silicon atoms may have been redistributed to form Si-C bonding while the excess energy was released as heat to promote the formation of nanoclusters but graphitize the sp3 bonding in DLC. Although sp3 bonding was reduced with the presence of copper, mechanical characterization showed that the adhesion strength of the composite films was approximately five times higher compared to undoped DLC, as a result of the decrease in internal stress and the formation of Si-C bondings in DLC. © 2011 Materials Research Society.