Diffusion of silicon in Pd2Si during silicide formation

Abstract
Inert and radioactive markers have been used to study the mechanism of diffusion during Pd2Si formation. With the aid of Ti as an inert marker it has been shown that silicon is the dominant diffusing species during polycrystalline Pd2Si formation. When radioactive silicon is used as a marker it is found that the radioactive silicon is uniformly distributed throughout the Pd2Si after silicide formation. The self‐diffusion of silicon in Pd2Si was investigated and found to be much lower than that necessary to produce a uniform radioactive silicon distribution, had silicon diffused by a grain boundary or pure interstitial mechanism. It is therefore proposed that silicon diffuses by a vacancy mechanism during silicide formation.