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Rare Metals

, Volume 36, Issue 3, pp 193–197 | Cite as

Microstructure and mechanical property of Sn–Ag–Cu solder material

  • Yi-Gang Kong
  • Zhi-Gang Kong
  • Feng-Min Shi
Article
  • 163 Downloads

Abstract

Among the lead-free solder materials, Sn–Ag–Cu alloys have many advantages, such as good wetting property, superior interfacial properties and high creep resistance. In this article, the organization and welding performance of Sn–Ag–Cu material were investigated. The surface morphology of the two alloys was observed by stereoscopic microscope and scanning electron microscope (SEM). Chemical constitution was examined by X-ray energy-dispersive spectroscopy (EDS). The mechanical properties of Sn–Ag–Cu solder were evaluated systematically compared with those of Sn–Cu solder. The results show that Sn–Ag–Cu solder based on different solder pads has different welding properties. The thickness of intermetallic compound (IMC) at the interface increases with aging time. For the gold-plated pads, there are a large number of IMC graphic, and in the welding interface, it can reduce the reliability of electrical connection. The Sn–Ag–Cu solder joints show a superior mechanical property over the traditional Sn–Cu solder. The number of dimples decreases and that of cavities increases for Sn–Cu0.7 alloy and the fracture surfaces of Sn–Ag3.0–Cu0.5 alloy have many small size dimples which are homogeneously distributed.

Keywords

Lead-free solder Organization Welding performance Intermetallic compound 

Notes

Acknowledgments

This study was financially supported by the Chinese Universities Scientific Fund (No. 2013RC0402), the Science & Technology Planning Project of Jinan City, China (No. 201401056), the Natural Science Foundation of Shanxi Province, China (No. 2013011023-5), and the Taiyuan University of Science & Technology Doctoral Fund (No. 20122029).

References

  1. [1]
    Gourlay CM, Read J, Nogita K. The maximum fluidity length of solidifying Sn–Cu–Ag–Ni solder alloys. J Electron Mater. 2012;37(1):51.CrossRefGoogle Scholar
  2. [2]
    Ventura T, Nogita K. The influence of 0–0.1 wt% Ni on the microstructure and fluidity length of Sn–0.7Cu–xNi. J Electron Mater. 2008;37(1):32.CrossRefGoogle Scholar
  3. [3]
    Pang HL, Xiong BS. Low cycle fatigue study of lead free 99.3Sn–0.7Cu solder alloy. Int J Fatigue. 2004;26(5):865.CrossRefGoogle Scholar
  4. [4]
    Zribi A, Clark A, Zavalij L. The growth of intermetallic compounds at Sn–Ag–Cu solder/Cu and Sn–Ag–Cu solder/Ni interfaces and the associated evolution of the solder microstructure. J Electron Mater. 2001;30(9):1157.CrossRefGoogle Scholar
  5. [5]
    Xu BS, Zang LK, Yuan ZF, Wu Y, Zhou Z. Dissolutive wetting process and interfacial characteristic of molten Sn–17Bi–0.5Cu alloy on copper substrate. Rare Met. 2013;32(6):537.CrossRefGoogle Scholar
  6. [6]
    Amalu EH, Lau WK, Ekere NN. A study of SnAgCu solder paste transfer efficiency and effects of optimal reflow profile on solder deposits. Microelectron Eng. 2011;88(7):1610.CrossRefGoogle Scholar
  7. [7]
    Naoyuki H, Tokuteru U, Yorinobu T. Effects of Zn addition and aging treatment on tensile properties of Sn–Ag–Cu alloys. J Alloy Compd. 2012;527(25):226.Google Scholar
  8. [8]
    Nogita K, Read J, Nishimura T. Microstructure control in Sn–0.7 mass% Cu alloys. Mater Trans. 2005;46(11):2419.CrossRefGoogle Scholar
  9. [9]
    Fakpan K, Otsuka Y, Mutoh Y. Creep-fatigue crack growth behavior of Pb-contained and Pb-free solders at room and elevated temperatures. Procedia Eng. 2011;10(5):1238.CrossRefGoogle Scholar
  10. [10]
    Jiang L, Chawla N. Mechanical properties of Cu6Sn5 intermetallic by micropillar compression testing. Scripta Mater. 2010;63(4):480.CrossRefGoogle Scholar
  11. [11]
    Jeong WY, Won CM, Seung JB. Interfacial reaction of ENIG/Sn–Ag–Cu/ENIG sandwich solder joint during isothermal aging. Microelectron Eng. 2006;83(6):2329.Google Scholar
  12. [12]
    Ochoa F, Deng X, Chawla N. Effects of cooling rate on creep behavior of a Sn–3.5 Ag alloy. J Electron Mater. 2004;33(12):1592.CrossRefGoogle Scholar
  13. [13]
    Wang JX, Xue SB, Fang DS, Zhang ZS. Effect of diode-laser parameters on shear strength of micro-joints soldered with Sn–Ag–Cu lead-free solder on Au/Ni/Cu pad. Trans Nonferrous Metals Soc China. 2006;16(6):1374.CrossRefGoogle Scholar
  14. [14]
    Nianduan L, Donghua Y, Liang L. Interfacial reaction between Sn–Ag–Cu solder and Co–P films with various microstructures. Acta Mater. 2013;61(2):4581.Google Scholar
  15. [15]
    Kim KS, Huh SH, Suganuma K. Effects of intermetallic compounds on properties of Sn–Ag–Cu lead-free soldered joints. J Alloy Compd. 2009;352(2):226.Google Scholar
  16. [16]
    Shiau LC, Ho CE, Kao CR. Reactions between Sn–Ag–Cu lead-free solders and the Au/Ni surface finish in advanced electronic packages. Solder Surf Mount Technol. 2002;14(3):25.CrossRefGoogle Scholar
  17. [17]
    Nishikawa H, Piao JY, Takemoto T. Interfacial reaction between Sn–0.7Cu solder and Cu substrate. J Electron Mater. 2006;35(5):1127.CrossRefGoogle Scholar
  18. [18]
    Ma D, Wang WD, Lahiri SK. Scallop formation and dissolution of Cu–Sn intermetallic compound during solder reflow. J Appl Phys. 2012;91(5):3312.CrossRefGoogle Scholar

Copyright information

© The Nonferrous Metals Society of China and Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.School of Mechanical EngineeringTaiyuan University of Science and TechnologyTaiyuanChina
  2. 2.Research Laboratory of Electrical ContactsBeijing University of Posts and TelecommunicationsBeijingChina
  3. 3.Technology DepartmentJinan No. 10 Radio Factory Co., Ltd.JinanChina

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