Effect of Pulsed Substrate Bias on Evolution of Surface Morphology and <i>s</i><i>p</i><sup>3</sup> Hybridization Degree of Ag-DLC Films in a Mid-Frequency Dual-Magnetron Sputtering

Abstract

In this work, we have investigated the influence of the pulsed substrate bias voltage on the evolution of the surface morphology and sp3 hybridization degree of Ag containing diamond-like carbon (Ag-DLC) films deposited by using a mid-frequency dual-magnetron sputtering system. The unipole substrate bias voltage at 0 V, -60 V, -100 V and -150 V, respectively, was employed on AISI 440 substrate with the duty ratio uniformly set at 70%. The surface morphology was observed by AFM and the hybridization degree of the DLC films was performed respectively using Raman Spectroscopy and Rockwell C indenter. In these samples, the surface morphology and sp3 hybridization degree of Ag-DLC films show a certain dependence on the pulsed substrate bias applied. The evolution tendency of the surface morphology is found different with that of the sp3 hybridization degree of the DLC films under action of the pulsed substrate bias. These phenomena imply that the energetic particles may induce a balance between recombination of the particles and change of the internal stress in the DLC films.