关键词: 高保真有限元建模, 湿扩散, 均匀化方法

Abstract: To meet the demands for high environmental adaptability and high integration in the field of integrated circuits, research on the moisture reliability and multi-scale issues of packaging devices is particularly crucial. The high-density metal routing and layout of electronic packaging structures are the primary factors that affect moisture diffusion. Taking typical integrated circuit packaging structures as the research object, a high-fidelity finite element modeling method based on packaging structure layout is employed to precisely characterize the influence of the distribution of complex interconnect structures on moisture diffusion pathways within the package. Based on the mathematical similarity between Fick’s diffusion equations and the heat conduction equation, the heat conduction analysis module in the finite element analysis (FEA) software is employed to analogically simulate the moisture diffusion behavior in organic packaging materials and metallic materials. The high-fidelity finite element modeling method faces the trade-off between modeling accuracy and computational efficiency when enhancing the resolution of packaging structure layout. It is verified that by controlling the resolution within the range of 100×100 to 200×200, the modeling time is significantly reduced to 6.044% of the 425×425 high-resolution model, while retaining high computational accuracy. Simulation results show that the diffusion behavior of moisture within the packaging structure is guided by the distribution characteristics of moisture-insulating materials. The method can be developed and applied to three-dimensional stacked structures, and can provide guidance for the optimization design of structural layout for improving the moisture resistance of electronic packaging devices.

Key words: high-fidelity finite element modeling, moisture diffusion, homogenization method