Simulation of mechanical response of solder joints under drop impact using equivalent layer models

This paper presents equivalent layer models (including the full equivalent layer model and the hybrid layer model) for performing simulation of the mechanical response of solder joints under drop impact. In these models, a 3D anisotropic continuum layer is used to represent the array of discrete solder joints, in order to save computational time and memory. A detailed model with a fine mesh is used as a benchmark to assess the accuracy of the simplified equivalent layer models. An electronic package with 10,000 interconnects undergoing drop impact is examined. The simulation on the drop impact of packages with underfill is also studied. Excellent correlation is obtained between the equivalent and detailed models. It is shown that by using this new equivalent model, the model size and computational processing time can be greatly reduced, while maintaining the accuracy of the results.