Lattice imaging of silicide-silicon interfaces

Abstract

The interfaces of both epitaxial and non-epitaxial silicides and silicon were investigated by the direct lattice imaging method using cross-sectional samples. Non-epitaxial CoSi2 on silicon was observed to have a curved interface. Epitaxial CoSi2, however, was found to be smooth withib a facet. No evidence of an amorphous layer at the interface was obtained. Epitaxial NiSi2 on Si(001) was found to be heavily faceted. The facets are on {111} and {100} planes with the former more frequently observed. The interface between Si(111) and NiSi2 is also faceted but less so than that for Si(001). The interface is very rough on a large scale. Straight boundary lines corresponding to faceted planes were observed which indicated that the interfaces on an atomic scale were quite smooth. Defect clusters and planar defects were also observed at the interfaces. © 1982.