Interdiffusion and reaction in Cu/PtSi/Si(100) systems

Abstract

Interdiffusion and reaction in Cu/PtSi/Si(100) structures have been investigated. During annealing Cu migrates across the intermediate PtSi layer and reacts with Si to form Cu silicides, with no indication of PtSi decomposition or a Cu-PtSi reaction. The diffusion of Cu through PtSi proceeds nonuniformly when PtSi is exposed to air before Cu deposition. Uniform transport is observed when the sample is prepared in situ without breaking vacuum. Cu silicides grow linearly with time, while the rates are independent of the thickness of the transport medium. The results indicate that Cu silicide formation is not controlled by Cu diffusion through the interposed PtSi layer.