In this article, the filler distribution in an epoxy molding compound (EMC), used in IC packaging, is studied across a wafer using high-resolution X-ray computed tomography (HR-XCT). It is widely assumed that the fillers are uniformly distributed across the wafer. However, it is demonstrated that the distribution of the filler deviates across the wafer and that filler sizes affect the distribution on edge and center of wafer too. Quantitative HR-XCT of the filler distribution provides accurate data for simulation. Based on this approach, the differences between the coefficient of thermal expansion (CTE) and Young’s modulus values of the filler material for the center and edge of the wafer are explained. Furthermore, compression simulations are conducted by applying an XCT-based finite element method (FEM) model to understand the role of EMC for the mechanical behavior of advanced IC packages. These findings are validated by in situ and stand-alone compression experiments. The accurate simulation results demonstrate that the use of an XCT-based FEM model provides insight into the mechanical behavior of the EMC itself and, furthermore, of the whole IC package.

中文翻译：

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使用高分辨率X射线计算机断层扫描技术测定环氧模塑化合物中的填料分布

在本文中，使用高分辨率X射线计算机断层扫描（HR-XCT）研究了用于IC封装的环氧模塑化合物（EMC）中填料的分布。人们普遍认为填料在晶片上均匀分布。然而，已证明填料的分布在整个晶片上有偏差，并且填料的尺寸也影响晶片的边缘和中心的分布。填充物分布的定量HR-XCT为仿真提供了准确的数据。基于这种方法，说明了用于晶片中心和边缘的填充材料的热膨胀系数（CTE）和杨氏模量值之间的差异。此外，通过应用基于XCT的有限元方法（FEM）模型进行压缩仿真，以了解EMC在高级IC封装的机械性能中的作用。这些发现得到了以下方面的验证：原位和独立的压缩实验。准确的仿真结果表明，使用基于XCT的FEM模型可以深入了解EMC本身以及整个IC封装的机械性能。