高密度封装倒装焊的新简化模型及疲劳寿命分析  

New Simplified Model and Fatigue Life Analysis of Flip Chip Welding for High Density Packaging

作　　者：崔新雨 单月晖 沈飞 柯燎亮 苏洁 CUI Xinyu;SHAN Yuehui;SHEN Fei;KE Liaoliang;SU Jie(School of Mechanical Engineering,Tianjin University,Tianjin 300350,China;Institute in Equipment Development,Beijing 100034,China)

机构地区：[1]天津大学机械工程学院,天津300350 [2]军委装备发展部某中心,北京100034

出　　处：《力学季刊》2023年第1期65-74,共10页Chinese Quarterly of Mechanics

基　　金：国家自然科学基金杰出青年科学基金(11725207)。

摘　　要：高密度封装结构中存在大量焊球,在进行有限元建模时,考虑到焊球数量多且尺寸小的特点,需简化焊球层模型.本文针对高密度封装结构中倒装焊及底填胶,提出了一种新的简化模型,采用非重点部位简化和材料均匀化相结合的方法,将内部焊球层和底填胶简化为均匀层,只保留外圈几层焊球.通过建立代表性体积单元,计算得到均匀化层的材料参数.讨论了外层焊球圈数对焊球层危险点应力的影响,发现保留外圈两层焊球就能得到非常精确的结果.利用新简化模型计算了高密度封装结构的疲劳寿命,所获得的结果与未均匀化模型结果误差在0.3%以内.There are a large number of solder balls in high-density packaging structure.When considering the characteristics of large number and small size of solder balls in finite element simulation,it is necessary to simplify the solder ball layer model.In this paper,a new simplified model is proposed for flip chip welding and underfill in high-density packaging structures.The method of combining the simplification of non-key parts with the material homogenization is used to simplify the internal solder ball layer and underfill into a uniform layer,and only retains several layers of solder balls in the outer ring.The material parameters of the homogenized layer are calculated by establishing a representative volume element.The influence of the number of outer welding balls on the stress at dangerous points in the welding ball layer is discussed.The fatigue life of high-density packaging structure is calculated by using the new simplified model,and the error of between the new model and original model is within 0.3%.

关 键 词：高密度封装 倒装焊 材料均匀化 热疲劳寿命 

分 类 号：O343.6[理学—固体力学]