Nucleation-controlled thin-film interactions: Some silicides

Silicides formed by the interaction of a metal thin film with a single-crystal silicon substrate usually grow in layers according to diffusion- or reaction-controlled kinetics. The mechanism of the formation of five silicides, IrSi3, Rh4Si5, Hf Si2, NiSi2, and PdSi, share common aspects which set them categorically apart from IrSi1.75, RhSi, HfSi, NiSi, and Pd2Si, which form in the usual way. It is proposed that the nucleation process of IrSi 3, Rh4Si5, HfSi2, NiSi2, and PdSi results from the respective small driving forces and the ensuing importance of usually negligible stress and/or surface effects.