Thermal behavior of silver nanoparticles for low-temperature interconnect applications

Low-temperature sintering behavior of Ag nanoparticles was investigated. The nano Ag particles used (similar to20 nm) exhibited obvious sintering behavior at significantly lower temperatures (similar to150degreesC) than the T-m (960degreesC) of silver. Coalescence of the nano Ag particles was observed by sintering the particles at 150degreesC, 200degreesC, and 250degreesC. The thermal profile of the nanoparticles was examined by a differential scanning calorimeter (DSC) and a thermogravimetric analyzer (TGA). Shrinkage of the Ag-nanoparticle compacts during the sintering process was observed by thermomechanical analysis (TAU). Sintering of the nanoparticle pellet led to a significant increase in density and electrical conductivity. The size of the sintered particles and the crystallite size of the particles increased with increasing sintering temperature.