Three-dimensional atomic-scale mapping of Pd in Ni 1 − x Pd x Si ∕ Si ( 100 ) thin films

Atom-probe tomography was utilized to map the three-dimensional distribution of Pd atoms in nickel monosilicide thin films on Si(100). A solid-solution Ni 0.95 Pd 0.05 film on a Si(100) substrate was subjected to rapid thermal processing plus steady-state annealing to simulate the thermal processing experienced by NiSi source and drain contacts in standard complementary metal-oxide-semiconductor processes. Pd is found to segregate at the ( Ni 0.95 Pd 0.05 ) Si ∕ Si ( 100 ) heterophase interface, which may provide a previously unrecognized contribution to monosilicide stabilization. The silicide-Si heterophase interface was reconstructed in three dimensions on an atomic scale and its chemical roughness was evaluated.