Equivalent Modeling of Microbump Layer in Microsystem for Thermal Analysis Based on Differential Idea

The through-silicon-vias (TSV) packaging structure in the microsystem is complex, especially there are a large number of microbumps. Meanwhile, the microsystem structure size has a cross-scale problem. Then, detailed modeling will bring difficulties in meshing and simulation calculation efficiency. Based on the actual bump structure in the microbump layer, a calculating method for the anisotropy equivalent thermal conductivity of the microbump layer is proposed by using differential ideas combined with the heat transfer theory. The thermal simulation analysis of the detailed model and the equivalent model is completed. The comparison simulation results show that the equivalent modeling method has high accuracy and greatly calculation efficiency. By comparing the thermal test result, the simulation result is basically consistent with the test result, which verified the accuracy of the equivalent modeling method again. Later, the influence of the bump radius, the bump pitch, and the microbump layer height on the equivalent thermal conductivity of the microbump layer is mainly studied, which provides theoretical support on thermal design for the microbump layer in the microsystem.