With the reduction of size of electronic devices and solder interconnects, the current density is increasing rapidly and the electromigration effect becomes more critical to the interconnect failure. Traditional methods to determine the failure mechanism of interconnects are no longer sufficient under such high current densities. The electromigration effect upon failure mechanism of interconnect under high current density is discussed in this paper. A kinetic mass diffusion model is developed to predict void width and propagation speed near the interface between the intermetallic compound (IMC) and solder caused by eletromigration. 3D Finite element analysis has been implemented to analyze the current crowding effect around the void tip. The proposed kinetic model gives reasonable prediction for the void width and propagation velocity as compared with experimental results.