Role of Sandwich Cu Layer in and Effect of Self-Bias on Nanomechanical Properties of Copper/Diamond-Like Carbon Bilayer Films
The role of sandwich Cu layer in and effect of self-bias on structural and nanomechanical properties of Cu/DLC bilayer films have been explored. Cu/DLC bilayer films were grown, under varied self-bias from −125 to −225 V, using hybrid system involving radio-frequency- (RF-) plasma-enhanced chemical vapor deposition and RF-sputtering units. Surface topography and mean roughness was studied by atomic force microscope and then correlated with mechanical properties. The addition of sandwich Cu layer in DLC reduces its residual stress and does not affect bilayer film hardness and elastic modulus. Load versus displacement was also employed to estimate various other mechanical parameters, which further correlated with self-bias and structural properties. These Cu/DLC bilayer films seem to be a potential candidate for various industrial applications such as hard and protective coating on cutting tools, solar cells, and wear resistance coating on magnetic storage media.