The research on the resistance of electromigration of different connection form

Abstract

For the purpose to start the requirement on the mechanical and the electromigration reliabilities, this paper take the study on the electromigration on Cu Column Grid Array(CuCGA) and Ball Grid Array(BGA). In order to eliminate the influence by the heat migration, the study build and simulate the two models which contain the distribution of current density and temperature of the two connection form by using the software MSC.MARC. Then design the one integrated circuit to fulfill the current density which is more than 10 4 A/cm 2 . And take the experiment that the current density is 1.21×10 3 A/cm 2 , the electric time is 0h，50h， 100h，150h，200h respectively. Take and observe the metallographic diagram at last. The result shows that the peak value on current density and temperature appear at the joint interface between pad and solder. The peak value of current density and temperature of CuCGA is higher than BGA's since the average current density on pad is same. While the average current density keeps 1.21×10 3 A/cm 2 , the resistance on electromigration of CuCGA joints is weaker than the BGA's joints.