Optimization of a two-step Ni(5% Pt) germanosilicidation process and the redistribution of Pt in Ni(Pt)Si1−xGex germanosilicide

• A two-step Ni–Pt (5 at%) germanosilicidation process was optimized.
• Accumulation of Pt at the surface and Ni(Pt)Si1−xGex/SiGe interface is evidenced.
• Accumulation of Ge at the surface and Ni(Pt)Si1−xGex/SiGe interface is evidenced.
• Ge accumulation is caused by Ge out-diffusion from Ni(Pt)Si1−xGex grains.
• Pt redistribution is interpreted by a proposed tentative model of Pt diffusion.

Ni(Pt)Si1−xGex films with 5 at% Platinum (Pt) were prepared using a two-step annealing scheme. By monitoring the variation of sheet resistance (Rsh) with the Rapid Thermal Annealing (RTA) temperature, an optimal germanosilicidation process i.e. RTA1 at 300 °C/60 s and RTA2 at 400 °C/30 s was determined. The as-prepared Ni(Pt)Si1−xGex films were examined by means of X-ray diffraction (XRD) for crystallinity, cross-sectional transmission electron microscope (X-TEM) for morphology, Energy dispersive X-ray (EDX) element mapping and line-scanning for the element distribution. In order to elucidate the redistribution of Pt in the germanosilicide films, a tentative model of Pt diffusion during the Ni(Pt) germanosilicidation process is proposed which is in good agreement with the experimental results.