Structure and Mechanical Properties of Ti/C Multilayer Films Deposited by Sputtering

Abstract

We have deposited Ti/C multilayer films onto glass and Si wafer substrates by dc magnetron sputtering. The structure and the mechanical properties of multilayer films with various periods have been investigated. The multilayer films, of which periods were longer than 1.16 nm, showed diffraction peaks in low angle XRD patterns corresponding to their artificial layered structure. The Ti layer in the multilayer film was found to be amorphous when the period was less than about 5 nm. The roughness of Ti/C interface appeared to be larger than that of W/C multilayer system, which should be caused by a tendency of Ti layer to grow with a columnar structure. The hardness of Ti/C multilayer films was found to be constant when the period was larger than 2 nm. As the period decreased less than 2 nm, the hardness increased rapidly and reached nearly to the hardness of TiC single layer films. This should be caused by the increase in relative quantity of Ti-C bonds in the films.