STUDY OF DLC SILICON INTERFACES BY XPS AND INSITU ELLIPSOMETRY

The influence of silicon substrate cleaning prior to the deposition of diamond-like carbon films has been investigated as well as the composition of the coating/substrate interface which governs the adhesion of the deposits. Three different cleaning procedures have been used: argon plasma cleaning, CF4 dry etching and HF wet cleaning. In-situ ellipsometry has provided real-time evolution of the surface and interface during the plasma treatment and XPS analysis has been used to get information about the chemical structure of the interface. Ar cleaning has induced silicon lattice damages and the native oxide was not etched. The oxide removal is achieved using CF4 dry etching. Moreover CF4 overetching leads to Si-C bond formation.