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Electronic Materials Letters

, Volume 14, Issue 6, pp 678–688 | Cite as

Oxidation and Repeated-Bending Properties of Sn-Based Solder Joints After Highly Accelerated Stress Testing (HAST)

  • Jeonga Kim
  • Cheolho Park
  • Kyung-Mox Cho
  • Wonsik Hong
  • Jung-Hwan Bang
  • Yong-Ho Ko
  • Namhyun KangEmail author
Article
  • 361 Downloads

Abstract

The repeated-bending properties of Sn–0.7Cu, Sn–0.3Ag–0.7Cu (SAC0307), and Sn–3.0Ag–0.5Cu (SAC305) solders mounted on flexible substrates were studied using highly accelerated stress testing (HAST), followed by repeated-bending testing. In the Sn–0.7Cu joints, the Cu6Sn5 intermetallic compound (IMC) coarsened as the HAST time increased. For the SAC0307 and SAC305 joints, the Ag3Sn and Cu6Sn5 IMCs coarsened mainly along the grain boundary as the HAST time increased. The Sn–0.7Cu solder had a high contact angle, compared to the SAC0307 and SAC305 solders; consequently, the SAC0307 and SAC305 solder joints displayed smoother fillet shapes than the Sn–0.7Cu solder joint. The repeated-bending for the Sn–0.7Cu solder produced the crack initiated from the interface between the Cu lead wire and the solder, and that for the SAC solders indicated the cracks initiated at the surface, but away from the interface between the Cu lead wire and the solder. Furthermore, the oxide layer was thickest for Sn–0.7Cu and thinnest for SAC305, regardless of the HAST time. For the SAC solders, the crack initiation rate increased as the oxide layer thickened and roughened. Cu6Sn5 precipitated and grew along the grain and subgrain boundaries as the HAST time increased, embrittling the grain boundary at the crack propagation site.

Graphical Abstract

Keywords

Highly accelerated stress testing Solder joint Oxide Repeated-bending Flexible substrate 

Notes

Acknowledgements

This work was supported by the Technology Innovation Program (Grant No. 10051318, Development of SiC Automotive OBC Power Module with Environment-Friendly High-Temperature Bonding Materials) funded by the Ministry of Trade, Industry & Energy (MOTIE, Korea) and by the National Research Foundation of Korea (NRF), funded by the Korea government (MSIT) through GCRC-SOP (Grant no.2011-0030013).

References

  1. 1.
    Leen, G., Heffernan, D.: Expanding automotive electronic systems. Computer 35, 88–93 (2002)CrossRefGoogle Scholar
  2. 2.
    Han, C., Liu, Q., Ivey, D.G.: Electrochemical composite deposition of Sn–Ag–Cu alloys. Mater. Sci. Eng., B 164, 172–179 (2009)CrossRefGoogle Scholar
  3. 3.
    Official Journal of the European Union, Commission Directive 2011/37/EU amending Annex II to Directive 2000/53/EC on end-of-life vehicles (ELVDirective). http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2011:085:0003:0007:EN:PDF (2011)
  4. 4.
    European Parliament, Council of the European Union, Directive 2000/53/EC of the European Parliament and of the Council of 18 September 2000 on end-of life vehicles. https://eur-lex.europa.eu/legal-content/EN/ALL/?uri=CELEX:32000L0053 (2000)
  5. 5.
    Meola, C.: Pb-Free Electronics Research Manhattan Project, Phase I. ACI Technology Inc, Philadelphia (2009)Google Scholar
  6. 6.
    Chang, H., Cehn, H., Li, M., Wang, L., Fu, Y.: Generation of Tin(II) oxide crystals on lead-free solder joints in deionized water. J. Electron. Mater. 38, 2170–2178 (2009)CrossRefGoogle Scholar
  7. 7.
    Rosalbino, F., Angelini, E., Zanicchi, G., Carilini, R., Marazza, R.: Electrochemical corrosion study of Sn–3Ag–3Cu solder alloy in NaCl solution. Electrochim. Acta 54, 7231–7235 (2009)CrossRefGoogle Scholar
  8. 8.
    Wang, M., Wang, J., Ke, W.: Corrosion behavior of Sn–3.0Ag–0.5Cu lead-free solder joints. Microelectron. Reliab. 73, 69–75 (2017)CrossRefGoogle Scholar
  9. 9.
    Yokoyama, K., Tsuji, D., Sakai, J.: Fracture of sustained tensile-loaded Sn–3.0Ag–0.5Cu solder alloy in NaCl solution. Corros. Sci. 53, 3331–3336 (2011)CrossRefGoogle Scholar
  10. 10.
    Wang, M., Wang, J., Feng, H., Ke, W.: In-situ observation of fracture behavior of Sn–3.0Ag–0.5Cu lead-free solder during three-point bending tests in ESEM. Mater. Sci. Eng., A 558, 649–655 (2012)CrossRefGoogle Scholar
  11. 11.
    Rosalbino, F., Angelini, E.: Corrosion behaviour assessment of lead-free Sn–Ag–M (M = In, Bi, Cu) solder alloys. Mater. Chem. Phys. 109, 386–391 (2008)CrossRefGoogle Scholar
  12. 12.
    Bang, J.H., Yu, D.Y., Ko, Y.H., Yoon, J.W., Lee, C.W.: Lead-free solder for automotive electronics and reliability evaluation of solder joint. J. Weld. Join. 34(1), 26–34 (2016). (in Korean) CrossRefGoogle Scholar
  13. 13.
    Ko, Y.H., Yoo, S.Y., Lee, C.W.: Evaluation on reliability of high temperature lead-free solder for automotive electronics. J. Microelectron. Packag. Soc. 17(4), 35–40 (2010). (in Korean) Google Scholar
  14. 14.
    Hong, W.S., Oh, C.M.: Degradation behavior of solder joint and implementation technology for lead-free automotive electronics. J. Weld. Join. 31(3), 22–30 (2013). (in Korean) CrossRefGoogle Scholar
  15. 15.
    Park, J.Y., Kim, M.S., Oh, C.M., Do, S.H., Seo, J.D., Kim, D.K., Hong, W.S.: Solder joint fatigue life of flexible impact sensor module for automotive electronics. Korean J. Met. Mater. 55(4), 232–239 (2017). (in Korean) CrossRefGoogle Scholar
  16. 16.
    Pandher, R., Lawlor, T.: Effect of silver in common lead-free alloys. In: Proceedings of international conference on soldering and reliability, p. 86. Surface Mount Technology Association (SMTA), Toronto (2009)Google Scholar
  17. 17.
    Ochoa, F., Williams, J.J., Chawla, N.: Effects of cooling rate on the microstructure and tensile behavior of a Sn–3.5wt.%Ag solder. J. Electron. Mater. 32(12), 1414–1420 (2003)CrossRefGoogle Scholar
  18. 18.
    Li, D., Conway, P.P., Liu, C.: Corrosion characterization of tin–lead and lead free solders in 3.5 wt% NaCl solution. Corros. Sci. 50, 995–1004 (2008)CrossRefGoogle Scholar
  19. 19.
    Cho, S., Yu, J., Kang, S.K., Shin, D.Y.: Oxidation study of pure tin and its alloys via electrochemical reduction analysis. J. Electron. Mater. 34(5), 635–642 (2005)CrossRefGoogle Scholar
  20. 20.
    Zhao, J., Miyashita, Y., Mutoh, Y.: Fatigue crack growth behavior of 96.5Sn–3.5Ag lead-free solder. Int. J. Fatigue 23, 723–731 (2001)CrossRefGoogle Scholar
  21. 21.
    Ding, Y., Wang, C., Li, M., Bang, H.S.: In-situ SEM observation on fracture behaviors of Sn-based solder alloys. J. Mater. Sci. 40, 1993–2001 (2005)CrossRefGoogle Scholar
  22. 22.
    Park, Y., Bang, J.H., Oh, C.M., Hong, W.S., Kang, N.: The effect of eutectic structure on the creep properties of Sn–3.0Ag–0.5Cu and Sn–8.0Sb–3.0Ag solders. Metals 7(12), 540 (2017)CrossRefGoogle Scholar

Copyright information

© The Korean Institute of Metals and Materials 2018

Authors and Affiliations

  1. 1.Department of Materials Science and EngineeringPusan National UniversityBusanKorea
  2. 2.Components and Materials Physics Research CenterKorea Electronic Technology InstituteSeongnamKorea
  3. 3.Microjoining CenterKorea Institute of Industrial TechnologyIncheonKorea

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