填充不流动胶的倒装焊封装中芯片的断裂问题  

Die Cracking of Flip-Chip with No-Flow Underfill

作　　者：彩霞[1] 黄卫东[1] 徐步陆[1] 程兆年[1] 

机构地区：[1]中国科学院上海微系统与信息技术研究所中德联合实验室,上海200050

出　　处：《Journal of Semiconductors》2003年第1期90-97,共8页半导体学报（英文版）

基　　金：国家自然科学基金资助项目 (批准号 :1983 40 70 )~~

摘　　要：用断裂力学方法和有限元模拟分析了填充不流动胶芯片断裂问题 .模拟时在芯片上表面中心预置一裂缝 ,计算芯片的应力强度因子和能量释放率 .模拟表明 ,由固化温度冷却到室温时 ,所研究的倒装焊封装在填充不流动胶时芯片断裂临界裂纹长度为 12 μm,而填充传统底充胶时为 2 0 μm.模拟结果显示芯片断裂与胶的杨氏模量和热膨胀系数相关 ,与胶的铺展关系不大 .焊点阵列排布以及焊点位置也会影响封装整体翘曲和芯片断裂 .The die cracking with no-flow underfill is analyzed and compared with the case for conventional capillary-flow underfill.The fracture mechanics and finite element method are applied to the die cracking analysis of flip-chip assembly with no-flow underfill.The pre-crack is assumed at the center on the backside of the die in this simulation.The J integral is used to calculate fracture parameters,including energy release rate G and stress intensity factor K .The variation of fracture parameters with pre-crack lengths are simulated,and the critical length is about 12μm for the assembly with no-flow underfill and 20μm for the package with capillary-flow underfill at 20℃.The simulation results indicated that the die cracking is dependent on the Young's modulus and CTE of the underfill materials,but hardly on the underfill fillet.An interesting result from the case study of simulations is that the solder ball array and the ball locations would influence the warpage of packaging assembly and the die cracking.

关 键 词：填充 不流动胶 倒装焊封装 芯片 断裂 封装翘曲 能量释放率 应力强度因子 集成电路 

分 类 号：TN405.97[电子电信—微电子学与固体电子学]