Multiphysics Coupling Analysis and Structural Optimization of High Density TSVs in Microsystems

By using orthogonal parametric modeling and finite element simulation methods, the effects of TSV diameter, pitch and thickness of silicon interposer on the stress response of the silicon interposer structure under thermal-mechanical coupling conditions were investigated. The simulation results show that in the high temperature heat preservation stage, the maximum equivalent stress of the SiO2 isolation layer is located where it contacts the end face of the TSV, and the TSVs located on the four corners of the TSVs array have the largest equivalent stress. Compared with the thickness of the silicon interposer, the diameter and pitch of the TSV have the greatest influence on the maximum equivalent stress of the TSVs, and also have a greater effect on the stress superposition of the silicon interposer between the TSVs. When the diameter is 10μm, the pitch is 50μm and the thickness of the silicon interposer is 50μm, there has the smallest equivalent stress of the TSV silicon interposer structure, and the reliability of the TSV silicon interposer under thermal-mechanical coupling is also the highest. The results of this paper provide general conclusions and design suggestions for the subsequent structural and layout of TSV used in microsystems.