On the nucleation of PdSi and NiSi 2 during the ternary Ni(Pd)/Si(100) reaction

Schrauwen, A; Demeulemeester, J; Kumar, A; Vandervorst, W; Comrie, C M; Detavernier, C; Temst, K; Vantomme, A

On the nucleation of PdSi and NiSi 2 during the ternary Ni(Pd)/Si(100) reaction

Journal Article

2013

Journal Title

Journal of Applied Physics

Link to Journal

https://dx.doi.org/10.1063/1.4818333

Department

Department of Physics

Faculty

Faculty of Science

Abstract

During the solid phase reaction of a Ni(Pd) alloy with Si(100), phase separation of binary Ni- and Pd-silicides occurs. The PdSi monosilicide nucleates at temperatures significantly below the widely accepted nucleation temperature of the binary system. The decrease in nucleation temperature originates from the presence of the isomorphous NiSi, lowering the interface energy for PdSi nucleation. Despite the mutual solubility of NiSi and PdSi, the two binaries coexist in a temperature window of 100 °C. Only above 700 °C a Ni 1– x Pd x Si solid solution is formed, which in turn postpones the NiSi2 formation to a higher temperature due to entropy of mixing. Our findings highlight the overall importance of the interface energy for nucleation in ternary systems.