Numerical Analysis of Residual Warpage of FBGA Package during EMC Curing Process

摘要

In a semiconductor packaging process, the warpage greatly has influenced the reliability of the package as well as the workability. The strip warpage in FBGA package result from the structure of constitutes and the thermal mismatch by the thermo-mechanical properties such as coefficient of thermal expansion (CTE) and modulus of EMC, substrate, chip and adhesive materials. Therefore, the optimization of material properties and the package structure design has been needed by the numerical analysis. In this research, temperature dependent nonlinear thermal analysis was performed with the high temperature material properties and the result was compared with the actual measurement value. Optimization analysis of the strip warpage was also conducted. The main factors of the strip warpage were selected by design of experiment (DOE) process, and then the optimum conditions of design variables were obtained. Lastly, through the reliability analysis, the tolerances of design variables which can satisfy the limited conditions were proposed.