Korean Journal of Materials Research (한국재료학회지)

Materials Research Society of Korea (한국재료학회)
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Microstructures and Solderability of Multi-composition Sn-Cu Lead-free Solders

Sn-CU계 다원 무연솔더의 미세구조와 납땜특성

  • Kim Ju-Youn (Division of Materials Science and Engineering, Hanyang University) ;
  • Bae Kyoo-Sik (Dept. of Electronic Materials Engineering, The University of Suwon)
  • 김주연 (한양대학교 재료공학부) ;
  • 배규식 (수원대학교 전자재료공학과)
  • Published : 2005.09.01
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Abstract

To develope new lead-free solders with the melting temperature close to that of Sn-37Pb$(183^{\circ}C)$, Sn-0.7Cu-5Pb-1Ga, Sn-0.7Cu-5Pb-1Ag, Sn-0.7Cu-5Pb-5Bi-1Ag, and Sn-0.7Cu-SBi-1Ag alloys were composed by adding low-netting elements such as Ga, Bi, Pb, and Ag to Sn-0.7Cu. Then the melting temperatures, microstructures, wettability, and adhesion properties of these alloys were evaluated. DSC analysis showed that the melting temperature of Sn-0.7Cu-SPb-1Ga was $211^{\circ}C$, and those of other alloys was in the range of $192\~200^{\circ}C$. Microstructures of these alloys after heat-treatment at $150^{\circ}C$ for 24 hrs were basically composed of coarsely- grown $\beta-Sn$ grains, and $Cu_6Sn_5$ and $Ag_3Sn$ intermetallic precipitates. Sn-0.7Cu-5Pb-1Ga and Sn-0.7Cu-5Pb-5Bi-1Ag showed excellent wettability, while Sn-0.7Cu-5Bi-1Ag and Sn-0.7Cu-5Pb-5Bi-1Ag revealed good adhesion strength with the Cu substrates. Among 4 alloys, Sn-0.7Cu-5Pb-5Bi-1Ag with the lowest melting temperature $(192^{\circ}C)$ and relatively excellent wettability and adhesion strength was suggested to be the best candidate solder to replace Sn-37Pb.

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References

  1. S. K. Kang and A. K. Sarkhel, J. Electr. Mater., 23(8), 701 (1994) https://doi.org/10.1007/BF02651362
  2. S. W. Yoon, B-J. Lee and H. M. Lee, Korean Journal of Materials Research, 7(4), 303 (1997)
  3. S. K. Hong, C. H. Ju, C. Y. Kang and I. B. Kim, Korean Journal of Materials Research, 8( 11), 1011 (1998)
  4. M. L. Wu, D. Q. Yu, C. M. T. Law and L. Wang, Materials Science and Engineering R 44, I (2004) https://doi.org/10.1016/j.mser.2004.01.001
  5. S. Lee, W. H. Bang, J. P. Jung and K. H. Oh, J. Kor. Inst. Met. & Mater., 42(5), 448 (2004)
  6. H. M. Lee, Newsletter of Information Center for Materials, 7(6), 3 (2002)
  7. B. Trumble, IEEE Spectrum, 35(5), 55 (1998) https://doi.org/10.1109/6.669978
  8. Z. May and J. W. Morris, J. Electron. Mater., 21(6), 599 (1992) https://doi.org/10.1007/BF02655427
  9. J. B. Shim, K. K. Lee and D. J. Lee, Korean Journal of Materials Research, 8(1), 33 (1998)
  10. S-J. Kim and K-S. Bae, Korean Journal of Materials Research, 9(9), 926 (1999)