Study of phase separation in Ti-Co-N thin films on silicon substrate

Co27 and Ti73Co27- N during thermal annealing has been studied by SIMS, AES and XRD methods. It has been shown that in case of Ti73Co27 the CoSi2 layer was not formed and the formation of ternary silicide compounds CoTiSi and Co3Ti2Si took place. At the same time in case of Ti73Co27- N the bottom layer CoSi2 and the upper layer based on TiN were formed. The interaction behaviour has been found to depend on nitrogen concentration in initial film. For high amount of nitrogen the diffusion of Si atoms into upper layer and Si3N4 phase formation were observed. The possible variants of solid-phase interaction between silicon and the alloys containing intermetallic compounds and influence of nitrogen on this process are discussed.