Characterization of the microstructure of Co thin film on silicon substrate by TEM

The microstructure of as-deposited Co thin films on silicon (001) substrate was characterized by TEM using wedge-shaped planar-view samples. Selected area electron diffraction showed that the as deposited Co thin films were c omposed of Co (alpha) and that no interfacial reaction took place between C o thin films and the Si substrate. The microstructure of Co thin films anne aled at 250 degrees C for 30 min was also investigated by using conventiona l planar-view samples. The analysis of selected area electron diffraction i ndicates that Co thin films react entirely with the Si substrate, and a sil icide layer forms at the Co/Si interface. Dark field images clearly indicat e that the interfacial layer consists of Co2Si in irregular stripes and CoS i as fine particles but no CoSi2 forms.