Fracture mechanics analysis of solder joint intermetallic compounds in shear test

Among different parameters studied in this research, the location of the crack from the solder interfaces has been found to be very sensitive. Crack near 1 micron distance from the interface has been found to be very prone to propagate. It is interesting to see that a thicker IMC layer reduces crack propagation propensity if there is only a single crack exists in the IMC layer and that crack is located at the middle of the IMC layer. Even if the whole solder layer is replaced by the IMC in the solder joint, the fracture propagation possibility is greatly reduced. Thickness of solder joints is also found to have a significant influence on the SIF values. It has been found that soft solder matrix generates non-uniform plastic deformation across the solder-IMC interface near the crack tip that is responsible to obtain a wide range of KI, KII and θ values.