In situ investigation of the formation of an intermixed phase at the Ni/Si(100) interface by photoelectron spectroscopic methods

Photoemission experiments were performed systematically on Ni/Si(100) interfaces and amorphous alloys with different nickel coverages and content, respectively. Both valence-band spectra and analysis of core level spectroscopy of the Ni2p3/2 indicate the formation of a homogeneous intermixed, amorphous interface layer. The nickel content in this layer varies in a wide range with the nominal nickel coverage as long as the respective amorphous alloys exist. The interface reaction is terminated at a Ni concentration of about 75 at%, which coincides with the known upper stability limit for the amorphous alloy.