埋置空气隙柔性凸点结构随机振动应力应变分析

Random vibration stress and strain analysis of embedded air-gap compliant bump structure

机械振动疲劳失效是影响柔性晶圆级封装芯片互连结构可靠性的关键因素之一。应用埋置空气隙的柔性凸点结构进行随机振动条件下的有限元仿真分析,建立了三维有限元仿真模型,加载随机振动载荷后分析了X、Y、Z三个方向振动作用下各模态对应互连结构应力应变分布。研究结果表明,随机振动载荷条件下柔性凸点结构最大应力、应变分布位置出现在距离芯片中心最远位置处,互连结构所受应力、应变值均处于材料承受极限范围内,埋置空气隙柔性凸点结构能有效提高电子产品抗振疲劳可靠性。

Mechanical vibration fatigue failure is one of the critical factors affecting the reliability of the interconnected structure of flexible wafer-level packaging chips.The embedded air-gap compliant bump structure was adopted to FEM simulate and analyze under random vibration conditions.Three-dimensional finite element simulation model was established.After heat and vibration load were simultaneously applied,the stress and strain distribution of the interconnected structure was analyzed for each mode under the vibration of X,Y,and Z directions.The results show that the maximum stress and strain distribution of the compliant bump structure under compound load conditions appear at the farthest edge position from the chip center,and the stress and strain values of interconnected structure are within the material tolerance range.The anti-vibration fatigue reliability of electronic products can be improved effectively by adopting the embedded air-gap compliant bump structure.