摘要
针对典型的层叠封装建立了三维有限元模型,并采用有限元方法对封装在热循环载荷下的行为进行了数值模拟。在模拟计算中,Anand的粘塑性本构方程被用来描述SnAgCu焊球的力学行为。利用Engelmaier修正的Coffin-Masson疲劳公式对最易失效的焊球进行了寿命计算。结果表明,层叠封装中下层焊球的应力大于上层焊球,最易发生破坏的焊球位于下层阵列的边角处,模型中最危险焊球的寿命为791周。
A 3-D finite element model of PoP（Package on Package） was built,and the behavior of PoP subjected to thermal cycling was simulated using the finite element method.In the simulation,Anand＇s visco-plasticity constitutive equation was used to describe the mechanic behavior of SnAgCu solder balls.The fatigue life of the most dangerous solder balls was calculated using the Coffin-Masson formula modified by Engelmaier.The results show that the stress in the balls of the bottom array is higher than that in the balls of the top array.The most dangerous solder balls locate in corners of the bottom array,and their fatigue life is calculated to be 791 cycles.
出处
《电子元件与材料》
CAS
CSCD
北大核心
2011年第6期70-73,共4页
Electronic Components And Materials
基金
航空科学基金资助项目(No.20090246001)
关键词
层叠封装
有限元法
热疲劳寿命
Package on package（PoP）
finite element method
thermal fatigue life
