The intense bursts of heat released by explosively reacting multilayer foils can be controlled and used as heat sources in joining technologies. We use this method to produce Si/solder/Si joints to characterize the microstructure of the multilayer foil in the reacted state as well as the foil/solder interface. The resulting structure at the foil/solder interface is a nearly phase-separated, interlocking structure. The joint is tested using single lap shear Cu samples. Fracture surfaces have been analyzed and failure was observed to entirely occur within the solder layer.