Effect of aging time on microstructure and shear properties of Cu/In-Sn-2.5Ag/Cu solder joint

doi:10.13251/j.issn.0254-6051.2021.09.017

Abstract

Abstract: Microstructure and shear properties of the Cu/In-Sn-2.5Ag/Cu composite solder joint aged at 125 ℃ for different time were studied. The results show that the thickness of intermetallic compounds (IMCs) layer at the interface of the Cu/In-Sn-2.5Ag/Cu solder joint increases with the increase of aging time. Cu₆ (In, Sn)₅ phase is first formed at the interface, and a small number of Ag₉In₄ phases are produced in the solder. Cu₃(In, Sn) phase is generated by the further reaction of Cu atoms with the solder, and a part of Ag₉In₄ phase transforms into Ag₃In phase with the increase of aging time. The solder joint full of IMCs is formed when the aging time extends to 168 h. The shear strength of the solder joint increases first and then decreases with the increase of aging time. The shear strength reaches a maximum of 15.38 MPa when the aging time is 120 h.

Key words: Cu/In-Sn-2.5Ag/Cu solder joint, aging time, intermetallic compounds, shear strength

CLC Number:

TG156

Qiao Jian, Liu Zheng, Gao Huiming, Yang Li. Effect of aging time on microstructure and shear properties of Cu/In-Sn-2.5Ag/Cu solder joint[J]. Heat Treatment of Metals, 2021, 46(9): 104-107.

References

[1]张远辉, 王非森, 张安民. 瞬时液相扩散连接工艺参数及应用研究进展[J]. 热加工工艺, 2010, 39(9): 163-166.
Zhang Yuanhui, Wang Feisen, Zhang Anmin. Research progress on process parameters and application of transient liquid phase diffusion bonding[J]. Hot Working Technology, 2010, 39(9): 163-166.
[2]Wang F J, Zhou L L, Wang X J, et al. Microstructural evolution and joint strength of Sn-58Bi/Cu joints through minor Zn alloying substrate during isothermal aging[J]. Journal of Alloys & Compounds, 2016, 688: 639-648.
[3]Liu P, Yao P, Liu J. Effects of multiple reflows on interfacial reaction and shear strength of SnAgCu and SnPb solder joints with different PCB surface finishes[J]. Journal of Alloys and Compounds, 2009, 470(1-2): 188-194.
[4]杨东升. 三维封装芯片固液互扩散低温键合机理研究[D]. 哈尔滨: 哈尔滨工业大学, 2011.
Yang Dongsheng. Study on solid-liquid interdiffusion low temperature bonding mechanism of three-dimensional packaging chips[D]. Harbin: Harbin Institute of Technology, 2011.
[5]魏萌, 林建国, 吴为, 等. 连接温度对纯铜瞬时液相扩散连接接头组织及力学性能的影响[J]. 金属热处理, 2012, 37(9): 87-91.
Wei Meng, Lin Jianguo, Wu Wei, et al. Effect of bonding temperature on microstructure and mechanical properties of pure copper transient liquid phase diffusion bonding joint[J]. Heat Treatment of Metals, 2012, 37(9): 87-91.
[6]Tian S, Li S, Zhou J, et al. Effect of indium addition on interfacial IMC growth and bending properties of eutectic Sn-0.7Cu solder joints[J]. Journal of Materials Science: Materials in Electronics, 2017, 28(21): 16120-16132.
[7]Yeh M S. Effects of indium on the mechanical properties of ternary Sn-In-Ag solders[J]. Metallurgical & Materials Transactions A, 2003, 34(2): 361-365.
[8]Vianco P T, Hlava P F, Kilgo A C. Intermetallic compound layer formation between copper and hot-dipped 100In, 50In-50Sn, 100Sn, and 63Sn-37Pb coatings[J]. Journal of Electronic Materials, 1994, 23(7): 583-594.
[9]Wu Y, Sees J A, Pouraghabagher C, et al. The formation and growth of intermetallics in composite solder[J]. Journal of Electronic Materials, 1993, 22(7): 769-777.
[10]Deng X, Piotrowski G, Williams J J, et al. Influence of initial morphology and thickness of Cu₆Sn₅ and Cu₃Sn intermetallics on growth and evolution during thermal aging of Sn-Ag solder/Cu joints[J]. Journal of Electronic Materials, 2003, 32(12): 1403-1413.