Investigation of Thermo-mechanical and Phase-change Behavior in the Sn/Cu Interconnects during Self-Propagating Exothermic Reaction Bonding

Using the self-propagating exothermic reaction of nanoscale multilayer film can achieve effective bonding between solder and substrates at a much lower ambient temperature, but there are still many reliability issues which are yet to be understood. In this study, the Cu/Sn/Cu interconnect is prepared by using self-propagating exothermic reaction of Ni/Al nano-film, and the thermal transfer and mechanical response behavior of the Sn/Cu interconnect are investigated by numerical simulation. The work has taken into account the interaction between heat transfer and phase change, and coupling the influence of temperature on the thermal mismatch induced mechanical behavior. Furthermore, the results obtained from the macro-scale thermo-mechanical simulation are fed into a phase field model to predict the solidification microstructure of Sn during self-propagating exothermic reaction bonding.