Solid-phase reaction of Ni with amorphous SiGe thin film on SiO2

A study on the reaction of Ni and amorphous Si0.68Ge0.32 film on SiO2 is reported. The reaction was performed at 520 degrees C in a conventional furnace. The resulting film was characterized using X-ray photoelectron spectroscopy (XPS) and Raman scattering spectroscopy. Ni induced crystallization of SiGe was confirmed by the Raman spectra. XPS results indicate Ni piled up at or near the interface of the crystallized SiGe and the SiO2 substrate. The small amount of Ni inside the SiGe layer exists in more of a silicide-or germanide-like form. Ni enhanced oxidation of SiGe was found during the reaction and the oxidized layer was found to be a mixture of oxides of Si and Ge, with Ge piling up at the surface.