Microstructural properties of Ni-silicide films formed on epitaxially grown strained Si:P layer

As a future-generation source/drain contact structure, NiSi films were formed on a strained and epitaxial Si:P layer (P concentration of ~ 1.9 at.%), and their unique microstructural properties were characterized as a function of the annealing temperature (400–800 °C). Unlike the NiSi film formed on Si, those formed on the strained Si:P consisted of many abnormally large grains with a rather uniform thickness and flat-bottom interface, most likely because of the strain effect caused by the underlying Si:P layer. The strain energy built at the NiSi/Si:P interface is believed to have significantly affected the microstructure and morphology of the subsequently grown NiSi film, which eventually led to retardation of thermal agglomeration.