Diamond-like nanocompositef films fabricated in an acetylene atmosphere by ion beam assisted deposition: XPS analysis

摘要

Diamond-like nanocomposite (DLN) film, by embedding the diamond-like carbon into an amorphous SiO_2 network, is a special class of modifed diamond-like carbon (DLC) coating, which shows many excellent properties and potential applications. In this work, DLN films were fabricated in an acetylene atmospherre by ion beam assisted deposition. However, in order to understand the mechanical and electronic properties of the DLN film separation of the sp~3 carbon bond from sp~2 bond is necessary, becasue the former determines the hardness and the latter is related to the optical gap and electrical conductivity. Here we report the effect of the annealing on the relative concentrations of sp~3 and sp~2 hybrids in the film by using the XPS technique to decompose the C 1s signal into sp~3 and sp~2 components. The XPS results celearyl indicate that the distribution of the sp~3 and sp~2 C species is modified by thermal annealing at 700 deg C. More sp~3 species accumulate at the interface and gradually decrease towards the film surface.