Epitaxial Growth of Nickel Silicide NiSi₂on Silicon

Abstract

The formation of structures of nickel silicides on Si have been studied by the use of glancing angle X-ray diffraction, MeV4He+ backscattering, reflection electron diffraction and replica electron microscopy. By reacting evaporated Ni films with Si wafers in the temperature range of 200 to 800°C, we have found three Ni silicides. The phase Ni2Si starts to form at 200°C at the Si-Ni interface. Around 350°C, the phase NiSi grows from the Si-Ni2Si interface. The NiSi is stable in the temperature range of 350 to 750°C and above that it transforms abruptly to NiSi2. The disilicide grows epitaxially on (111), (110) and (100) surfaces of Si.