球形焊点三角形排列倒装芯片底部填充的能量法研究  

Study on the Underfill in Flip-Chip with Spherical Solder Bumps in Triangle Arrangement by Energy Method

作　　者：蒋伟杰 姚兴军[1] Jiang Weijie;Yao Xingjun(School of Mechanicai and Power Engineering,East China University of Science and Technology,Shanghai 200237,China)

机构地区：[1]华东理工大学机械与动力工程学院,上海200237

出　　处：《半导体技术》2021年第7期558-564,共7页Semiconductor Technology

基　　金：上海市自然科学基金资助项目(15ZR1409300)。

摘　　要：对于具有球形焊点且呈正三角形排列的倒装芯片,由于其待填充的空隙结构复杂,难以通过平均毛细压来建立底部填充的解析模型。因此通过能量变化来分析底部填充过程以避免平均毛细压的计算。首先分析了底部填充过程中表面能的变化、动能的变化和流道壁面对流动的阻力损耗;然后根据能量守恒定律得到了反映底部填充过程的新解析模型;最后用计算流体力学(CFD)软件对底部填充过程进行了三维数值模拟,以此验证了基于能量法的新解析模型。能量法更具有通用性,可用于研究焊点形状和排列方式复杂的倒装芯片底部填充过程。For a flip-chip with spherical solder bumps and equilateral triangle arrangement,it is difficult to establish an analytical model of underfill by the average capillary pressure due to the complex structure of the gap to be filled.Therefore,the underfill process was analyzed through the energy changes to avoid the calculation of the average capillary pressure.Firstly,the changes of surface energy and kinetic energy,and the resistance loss of the flow channel wall to the flow during the underfill process were analyzed.Then,a new analytical model reflecting the underfill process was obtained according to the law of energy conservation.Finally,the three-dimensional numerical simulation of the underfill process was carried out using computational fluid dynamics(CFD)software to verify the new analytical model based on the energy method.The energy method is more general and can be used to study the underfill process of flip-chip with complex solder bumps shapes and arrangements.

关 键 词：倒装芯片 底部填充 能量法 能量守恒 计算流体力学(CFD) 

分 类 号：TN305.94[电子电信—物理电子学]