Enhanced effects of Pt layer on thermal stability of NiSi thin film by solid phase reaction of Ni/Si (100) system

The solid phase silicification was studied on the thin films of Ni/Pt and Pt/Ni sputtered sequentially on Si (100) substrate. The results show that the phase transformation from NiSi to NiSi2 is delayed by the addition of l nm PT to the Ni/Si system as a cladding layer or an interlayer, and the phase transformation temperature is increased. As for the bilayered thin film system, XRD spectra indicate that there is no NiSi2 phase after annealing at 800°C, but some diffraction peaks corresponding to NiSi are observed after annealing at 850°C. Annealed at 800°C the film has a relative low resistance of 23-25μΩ&middotcm. Compared with the thermal stability of the NiSi film obtained by direct reaction of Ni with Si substrate, the thermal stability of the new film is increased by more than 100 °C, which favors the application of NiSi in the fabrication of Si-based devices.