Structural relationship of polycrystalline cobalt silicide lines to (001) silicon substrate

A local investigation of the structural properties of polycrystalline CoSi2 strips onto (001) Si wafers has been performed by transmission electron microscopy. CoSi2 crystal grains exhibit different behavior depending upon their position within the line. Grains close to the center of the strip are randomly oriented, while most of the grains at the edge of the strip grow epitaxially, obeying three different epitaxial relationships. Some of these grains maintain the substrate orientation with the presence of twin defects. High-resolution analysis demonstrates the presence of misfit dislocations at the CoSi2/Si interface, which accommodates the lattice mismatch.