PBGA封装体的热-结构数值模拟分析及其优化设计

基于热弹性力学和结构优化理论，针对典型的PBGA封装体在工作过程中的受热问题，建立了有限元数值模拟分析模型，模型中考虑了完全和部分两种焊点阵列形式，采用了基于散热功率的热生成加载、热循环加载和热循环、热生成综合加载三种方式．计算结果与文献中的实验结果进行了比较，并讨论了各层材料的主要参数对封装体热-结构特性的影响，算例结果表明对电子封装体的热-结构特性分析采用有限元数值模拟是可行的，并据此分别以最大应力最小化和封装体质量最轻为目标，对封装体进行了优化设计，为提高封装件的可靠性和优化设计提供了理论依据．

Thermo-structural stress analysis and optimization of PBGA package design

Based on the theory of thermal elasticity mechanics and structural optimization, the models of finite element numerical simulation for thermo-mechanical analysis of a plastic ball grid array(PBGA) package design are established.In models the finite element stress analysis of full-matrix and perimeter PBGA solder joint has been studied.The models are loaded by three modes,which are constant power generation in the die,accelerated thermal cycling and accelerated thermal cycling with superimposed constant power generation in the die.The effects of major components parameters of materials on thermo-mechanical stress are discussed.The numerical results are compared with the experimental results of literatures,and the results show that the finite element numerical simulation technique is feasible and effectual in the electronic package design.PBGA package optimization design is realized with the object of minimum mass and minimizing the maximum thermal stress.The results are expected to act as database for improving reliability of package and optimized design.