多物理场下FCBGA焊点电迁移失效预测的数值模拟研究

张元祥; 梁利华; 张继成; 陈俊俊; 盛玉峰

doi:10.6052/0459-1879-18-077

多物理场下FCBGA焊点电迁移失效预测的数值模拟研究

doi: 10.6052/0459-1879-18-077

1 衢州学院机械工程学院, 浙江衢州 324000
2 浙江工业大学机械工程学院, 杭州 310014

基金项目: 国家自然科学基金资助项目(51605252, 51375447).

详细信息

作者简介:
通讯作者:梁利华, 教授, 主要研究方向：计算固体力学和微电子封装技术研究. E-mail：lianglihua@zjut.edu.cn

通讯作者:
梁利华

中图分类号: O346,TN406;
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出版历程
- 收稿日期: 2018-01-30
- 刊出日期: 2018-05-18

MODELING OF ELECTROMIGRATION FAILURE PREDICTING FOR FCBGA SOLDER BUMP UNDER MULTI-PHYSICAL FIELD LOADS

1 College of Mechanical Engineering, Quzhou University, Quzhou 324000, Zhejiang, China
2 College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310014, China

摘要

摘要: 随着微电子封装技术的快速发展, 焊点的电迁移失效问题日益受到关注. 基于有限元法并结合子模型技术对倒装芯片球栅阵列封装(flip chip ball grid array, FCBGA)进行电-热-结构多物理场耦合分析, 详细介绍了封装模型的简化处理方法, 重点分析了易失效关键焊点的电流密度分布、温度分布和应力分布, 发现电子流入口处易产生电流拥挤效应, 而整个焊点的温度梯度较小. 基于综合考虑“电子风力”、温度梯度、应力梯度和原子密度梯度四种电迁移驱动机制的原子密度积分法, 并结合空洞形成/扩散准则及失效判据, 分析FCBGA焊点在不同网格密度下的电迁移空洞演化过程, 发现原子密度积分算法稳定, 不依赖网格密度. 采用原子密度积分法模拟真实工况下FCBGA关键焊点电迁移空洞形成位置和失效寿命, 重点研究了焊点材料和铜金属层结构对电迁移失效的影响. 结果表明, 电迁移失效寿命随激活能的增加呈指数级增加, 因此Sn3.5Ag焊点的电迁移失效寿命约为63Sn37Pb的2.5倍, 有效电荷数对电迁移寿命也有一定的影响;铜金属层结构的调整会改变电流的流向和焊点的应力分布, 进而影响焊点的电迁移失效寿命.
- 电迁移 /
- 电-热-结构耦合分析 /
- 互连焊点 /
- 失效寿命 /
- 空洞演化
Abstract: With the rapid development of microelectronics packaging technology, more attention has been paid to the electromigration (EM) failure on solder bump. The electric-thermal-structural multi-physical coupled analysis for flip chip ball grid array (FCBGA) packaging is performed in this paper based on FEM and submodeling technique. The simplified method of package model is introduced in detail. The current density distribution, temperature distribution and stress distribution of the key solder bump is investigated. It is found that the current crowding effect is easily generated at the location where electrons enter the bump from Cu metal layer, and the temperature gradient of the whole key solder bump is small. This paper presents the atomic density integral (ADI) method which considers four driving forces for electromigration such as electron wind force, stress gradient, temperature gradient and atomic density gradient. According to ADI method and the failure rule on void formation and diffusion, the electromigration void evolution process of the key solder bump is simulated with different mesh density. In can be found that the ADI method is stable and almost independent on the mesh density. The EM void location and time to failure (TTF) of key solder bump in FCBGA package is also simulated in the real service condition by ADI method. And the effect of solder material and Cu metal layer on EM failure is investigated in detail. We can see that the TTF of lead-free solder (Sn3.5Ag) is about 2.5 times than leaded solder (63Sn37Pb) because the TTF is determined to increase exponentially with the activation energy. And the EM failure is also influenced by the effective charge number. The adjustment of Cu metal layer structure will change the current flow direction and the stress distribution of the solder bump, which will affect the time to failure of solder bump.
- electromigration /
- electric-thermal-structural coupled analysis /
- solder bump /
- time to failure /
- void evolution

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参考文献(1)

[1]	刘勇, 梁利华, 曲建民. 微电子器件及封装的建模与仿真. 北京: 科学出版社, 2010: 3-4
[1]	(Liu Yong, Liang Lihua, Qu Jianmin.Modeling and Simulation of Microelectronic Devices and Packaging. Beijing: Science Press, 2010: 3-4 (in Chinese))
[2]	安彤,秦飞. 焊锡接点金属间化合物晶间裂纹的内聚力模拟. 力学学报, 2013, 45(6): 936-947
[2]	(An Tong, Qin Fei.Cohesive zone modeling of intergranular cracking of intermetallic compounds in solder joints.Chinese Journal of Theoretical and Applied Mechanics, 2013, 45(6): 936-947 (in Chinese))
[3]	Tu KN.Reliability challenges in 3D IC packaging technology.Microelectronics Reliability, 2011, 51(3): 517-523
[4]	ITRS. International technology roadmap for semiconductors, 2009 edition: Assembly and packaging. Technical report, ITRS, 2009
[5]	Lin EJ, Tang YK, Hsu YC, et al.Effect of Cu solubility on electromigration in Sn(Cu) micro joint.Journal of Applied Physics, 2017, 122(9): 095702
[6]	Gousseau S, Moreau S, Bouchu D, et al.Electromigration-induced failure in operando characterization of 3D interconnects: Microstructure influence.Microelectronics Reliability, 2015, 55(8): 1205-1213
[7]	Chen J, Liu K, Guo J, et al.Electromigration anisotropy introduced by tin orientation in solder joints.Journal of Alloys and Compounds, 2017, 703: 264-271
[8]	Tu KN.Recent advances on electromigration in very-large-scale-integration of interconnects.Journal of Applied Physics, 2003, 94(9): 5451-5473
[9]	He F, Tan CM.Circuit level interconnect reliability study using 3D circuit model.Microelectronics Reliability, 2010, 50(3): 376-390
[10]	Wang YX, Yao Y.A theoretical analysis of the electromigration-induced void morphological evolution under high current density. Acta Mechanica Sinica, 2017, 33(5): 868-878
[11]	熊骏, 李振环, 朱亚新等. 基于微结构动态演化机制的单晶镍基高温合金晶体塑性本构及其有限元模拟. 力学学报, 2017, 49(4): 763-781
[11]	(Xiong Jun, Li Zhenhuan, Zhu Yaxin, et al.Microstructure evolution mechanism based crystal-plasticity constitutive model for nickel-based superalloy and its finite element simulation.Chinese Journal of Theoretical and Applied Mechanics, 2017, 49(4): 763-781 (in Chinese))
[12]	Black JR. Mass transport of aluminum by momentum exchange with conducting electrons//Proceedings of the 6th Annual Reliability Physics Symposium, Los Angeles, California, 1967, Novmber 6-8. 148-159
[13]	Dalleau D, Weide-Zaage K.Three-dimensional voids simulation in chip metallization structures: A contribution to reliability evaluation.Microelectronics Reliability, 2001, 41(9-10): 1625-1630
[14]	Dalleau D, Weide-Zaage K, Danto Y.Simulation of time depending void formation in copper, aluminum and tungsten plugged via structures.Microelectronics Reliability, 2003, 43(9-11): 1821-1826
[15]	Weide-Zaage K.Simulation of migration effects in solder bumps.IEEE Transactions on Device and Materials Reliability, 2008, 8(3): 442-448
[16]	Liu Y, Liang LH, Irving S, et al.3D modeling of electromigration combined with thermal-mechanical effect for IC device and package.Microelectronics Reliability, 2008, 48(6): 811-824
[17]	Dandu P, Fan XJ, Liu Y.Some remarks on finite element modeling of electromigration in solder joints// 60th Electronic Components and Technology Conference, Las Vegas, NV, USA, 2010: 396-402
[18]	Tan CM, Hou YJ, Li W.Revisit to the finite element modeling of electromigration for narrow interconnects.Journal of Applied Physics, 2007, 102(3): 127
[19]	Liang LH, Zhang YX, Liu Y.Prediction of electromigration failure of solder joints and its sensitivity analysis.Journal of Electronic Packaging, 2011, 133(3): 031002
[20]	梁利华, 张元祥, 刘勇等. 金属互连结构的电迁移失效分析新算法. 固体力学学报, 2010, 31(2): 164-172
[20]	(Liang Lihua, Zhang Yuanxiang, Liu Yong, et al.A new algorithm for electromigration failure analysis of metal interconnects.Chinese Journal of Solid Mechanics, 2010, 31(2): 164-172 (in Chinese))
[21]	张元祥, 梁利华, 刘勇. 金属互连焊球的电迁移试验设计研究与灵敏度分析. 固体力学学报, 2011, 32(2): 158-166
[21]	(Zhang Yuanxiang, Liang Lihua, Liu Yong.Design of experiments and sensitivity analysis for electromigration on solder joints.Chinese Journal of Solid Mechanics, 2011, 32(2): 158-166 (in Chinese))
[22]	张元祥. 多物理场下金属微互连结构的电迁移失效及数值模拟研究. [博士论文]. 杭州: 浙江工业大学, 2011
[22]	(Zhang Yuanxiang.Electromigration failure analysis and numerical simulation of metal micro-interconnects under the multi-physical field. [PhD Thesis]. Hangzhou: Zhejiang University of Technology, 2011 (in Chinese))
[23]	梁利华, 张金超, 张元祥. 多场载荷作用下FCBGA焊点的电迁移失效研究. 工程力学, 2013, 30(9): 264-269
[23]	(Liang Lihua, Zhang Jinchao, Zhang Yuanxiang.Research of electromigration failure for FCBGA solder joint under the multi-physical field.Engineering Mechanics, 2013, 30(9): 264-269 (in Chinese))
[24]	张金超. 多场载荷交互作用下FCBGA焊点的电迁移失效研究. [硕士论文]. 杭州: 浙江工业大学, 2012
[24]	(Zhang Jinchao.Research of electromigration failure for FCBGA solder joints under multi-physical field. [Master Thesis]. Hangzhou: Zhejiang University of Technology, 2012 (in Chinese))
[25]	Basaran C, Lin M.Electromigration induced strain field simulations for nanoelectronics lead-free solder joints.International Journal of Solids and Structures, 2007, 44(14-15): 4909-4924
[26]	Basaran C, Abdulhamid MF.Low temperature electromigration and thermomigration in lead-free solder joints.Mechanics of Materials, 2009, 41(11): 1223-1241
[27]	Yao W, Basaran C.Electromigration damage mechanics of lead-free solder joints under pulsed DC: A computational model.Computational Materials Science, 2013, 71: 76-88.
[28]	Chang YW, Cheng Y, Xu F, et al.Study of electromigration-induced formation of discrete voids in flip-chip solder joints by in-situ 3D laminography observation and finite-element modeling.Acta Materialia, 2016, 117: 100-110
[29]	Alberti R, Enrici Vaion R, Mervic A, et al.Metal fatigue in copper pillar flip chip BGA: A refined acceleration model for the aluminium pad cracking failure mechanism.Microelectronics Reliability, 2015, 55(9-10): 1838-1842
[30]	Cheng S, Huang C, Pecht M.A review of lead-free solders for electronics applications.Microelectronics Reliability, 2017, 75: 77-95
[31]	Wang L, Xu C, Lin L, et al.Thermal stress analysis of the low-k layer in a flip-chip package.Microelectronic Engineering, 2016, 163: 78-82
[32]	Chen XL, Cheng J, Wu HW, et al.Open failure mechanisms of FCBGA package under temperature cycling stress// Proceedings of IEEE 24th International Symposium on the Physical and Failure Analysis of Integrated Circuits, Chengdu, 2017
[33]	Chen CI, Lee CC, Ni CY.Experimental and numerical investigations on solder reliability for flip-chip BGA packaging// Proceedings of IEEE International Conference on Service Operations and Logistics, and Informatics, Beijing, 2008: 2756-2762
[34]	Hsiao YC, Chih C.Enhancing Sn-Ag solder joints electromigration lifetime via the under-bump-metallization structure design// Proceedings of 10th Electronics Packaging Technology Conference, Singapore, 2008: 1144-1147
[35]	Chen CM, Chen SW.Electromigration effect upon the Sn/Ag and Sn/Ni interfacial reactions at various temperatures.Acta Materialia, 2002, 50: 2461-2469
[36]	Li Shidong.A multi-scale damage mechanics framework for nanoelectronics interconnects and solder joints. [PhD Thesis]. Buffalo: State University of New York, 2009
[37]	Jen MR, Liu LC, Lai YS.Electromigration on void formation of Sn3Ag1.5Cu FCBGA solder joints.Microelectronics Reliability, 2009, 49: 734-745