[en] We study the formation of nickel-germanosilicide (NiSiGe) on Sn ion pre-implanted Si_0_._8Ge_0_._2 layers. The Sn influences on NiSiGe morphology and sheet resistance are investigated at different annealing temperature. The NiSiGe films were characterized by scanning electron microscopy (SEM), Rutherford backscattering spectrometry (RBS), cross-section transmission electron microscopy (XTEM), and Energy Dispersive X-ray spectrometer (EDX) techniques. It is shown that the presence of Sn atoms increases the thermal stability of NiSiGe about 150 °C. We demonstrate that the Sn atoms retard the Ni germanosilicidation rate, stabilize the NiSiGe phase, and smooth the NiSiGe/SiGe interface.