Suppressing intermetallic compound growth in SnAgCu solder joints with addition of carbon nanotubes

In the present study, multi-walled carbon nanotubes (CNTs) were incorporated into SnAgCu solder matrix, to form composite solders. Isothermal aging study was performed on solder, joints, to investigate the formation and growth of the intermetallic compound (IMC) layer at the solder/metallization interface. Results revealed that after soldering, the initial interfacial IMC thickness of the unreinforced solder joint was comparable to that of the composite solder joints. However, after aging, the interfacial IMC layer of the unreinforced solder joint was observed to grow more significantly than that of the composite solder joints. Furthermore, the composite solder joints exhibited lower diffusion coefficient and this indicated that the presence of CNTs was effective in retarding the growth of the IMC layer.