Reactive diffusion in this system was studied, by using bulk-Pt/bulk-Si single-crystal diffusion couples, at temperatures ranging from 673 to 923K in a vacuum of 0.01Pa. In order to study the effect of the atmosphere upon the growth rate of the diffusion layers, some couples were annealed at 673, 873 and 923K under a pressure of 10-5Pa. In bulk couples which had been annealed at 673K for 1h or more, Pt2Si and PtSi were found. On the other hand, Pt3Si, Pt7Si3 and Pt6Si5 formed at temperatures above 723K. All of them grew according to a parabolic law. The interdiffusion coefficients of PtSi and Pt2Si in bulk samples almost coincided with the minimum values for thin-film couples; in spite of the general expectation that interdiffusion in thin-film couples would occur faster than in bulk samples at low temperatures.

T.Shimozaki, E.Yoshimura, Y.Wakamatsu, M.Onishi: Materials Transactions, 1995, 36[9], 1112-7