Mechanical Properties of Sintered Ag as a New Material for Die Bonding: Influence of the Density

Sintered silver powder is a good candidate for die bonding as an alternative to lead alloys. However, little is known about its intrinsic mechanical properties, which are required to model the entire electronic system reliability, especially during ageing. Since interconnections are obtained by sintering, the mechanical properties are expected to be impacted by the residual porosity. However, evaluating the density of the material in its 30-μm-thick form is challenging. This issue was addressed by developing a robust procedure to obtain bulk specimens with the same microstructure as the interconnection. Tensile tests were performed at room temperature to determine the macroscopic characteristics (Young’s modulus, ductility, yield stress, ultimate tensile stress) as a function of the porosity.