Stress analysis of plastic IC package containing various interface delaminations using the boundary element method

The purpose of this paper is to carry out stress calculation of the integrated circuit (IC) plastic package under the remote loading or the pressure acting on the delamination surfaces by the boundary element method (BEM). Based on symmetrical property of the problem geometry and the loading, the corresponding fundamental solution can be obtained to further reduce the number of the boundary elements used in the discretization of the problems. Near the interface delamination tips, singular boundary elements are used to accurately obtain the stress intensity factors. For the pre-assumed delamination spaces, the corresponding stress distributions in each domain can be obtained so that the effect of the interface delamination on the stresses can be observed. In order to assure the rightness of the developed code, some special problems in which the analytical solutions are available are studied. The results show that the developed code can produce numerical results with high accuracy.