Microstructural and Electrical Characteristics of Sintered Ag Interconnections through Different Reduction Methods

Taking the advantage of low sintering temperature and high processing flexibility, Ag nanoparticles have been widely used to fabricate interconnections and joints. This report studies the preferred orientation of the sintered nanoparticles and electrical resistivity subjected to thermal or/and chemical reductions using grazing incidence XRD and EBSD. Submicron-sized Ag powders prepared by thermal spray pyrolysis are also investigated for comparison. Compared to chemical reduction which develops (111) out-of-plane texture, thermal sintering of nanoparticles tends to form (100)-oriented grains and more twin boundaries. A decrease in sintered film thickness further intensifies (111) texture in the case of chemical sintering. A proportional relationship between electrical conductance and twin boundary ratio was also proposed.