Effect of AlN on the microstructure evolution of Cu/Sn58Bi/Cu solder joints for 3D packaging at different bonding times
Xi Wang, Liang Zhang, Chen Chen, Xiao Lu
Abstract
Cu/Sn58Bi/Cu and Cu/Sn58Bi-0.05AlN/Cu were prepared by transient liquid-phase bonding (TLP) bonding process for low temperature bonding and high temperature service. The evolution of interfacial IMC and the influence mechanism of AlN on TLP solder joints were studied. During the bonding process, the top and bottom IMC show asymmetric growth. With the increase of bonding time, Cu6Sn5 and Cu3Sn in the two solder joints continue to grow, and finally complete IMC morphology can be formed, of which Cu6Sn5 IMC is more and Cu3Sn IMC is less. In addition, by calculating the growth rate of Cu3Sn IMC, it was found that the growth rate of Cu3Sn IMC at both ends of the three-dimensional solder joint containing AlN is suppressed.