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Fundamentals of Solder Alloys in 3D Packaging

  • Kwang-Lung LinEmail author
Chapter
Part of the Springer Series in Advanced Microelectronics book series (MICROELECTR., volume 57)

Abstract

The demand of ever-improving functions of the electronic products has been pushing the development of Moore’s law featuring technologies. The microelectronic circuit technology has been moving towards the single digit nano era which is approaching the current technical limit. 3D packaging technology is being regarded as one of the most feasible technologies in this regard. The chips are being stacked in the 3D packaging so as to efficiently shrink the substrate landscape as well as shorten the circuit distance. The stacking relies on the thumb of art interconnect technologies which allow not only minimizing the substrate area but also the form factor of the products. One of the key interconnect technologies which has been improved to fit the need is the solder bumping. The conventional bumping technology of C4 is being moved to microbump with simplified solder compositions and shrunk solder volume. The dimension of the microbump may be one to three orders less than the C4 bump and BGA solder ball. The fast reaction between solder and the major metallization layers during reflow, thermal compressing bonding, and afterwards functioning results in the vast proportion of intermetallic compounds (IMC) in the smaller solder volume microjoint. The fundamentals to consider about for monitoring the reliability of the microbump will be different from the C4 bump which has large volume fraction of solder alloy. This chapter will discuss the IMC formation and the microstructure of the microbump at the as-produced, thermal cycled stages of the 3D packaging.

Keywords

Intermetallic Compound Solder Joint Solder Bump Kirkendall Void Cu3Sn Layer 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgment

The editors would like to thank Pilin Liu from Intel Corporation for his critical review of this chapter.

References

  1. 1.
    C.K. Lee, C.J. Zhan, J.H. Lau et al., Wafer bumping, assembly, and reliability assessment of μbumps with 5μm Pads on 10μm Pitch for 3D IC Integration. In 2012 I.E. 62nd Electronic Components and Technology Conference CPMT, San Diego, 29 May 2012–1 June 2012, p 636Google Scholar
  2. 2.
    J.W. Peng, Y.S. Chen, Y. Chen et al., Removed organic solderability preservative (OSPs) by Ar/O2 microwave plasma to improve solder joint in thermal compression flip chip bonding. In 2014 I.E. 64th Electronic Components and Technology Conference (ECTC ), CPMT, Lake Buena Vista, FL, 27–30 May 2014, p 1584
  3. 3.
    L. Panchenko, K. Croes, I. De Wolf et al., Degradation of Cu6Sn5 intermetallic compound by pore formation in solid-liquid interdiffusion Cu/Sn microbump interconnects. Microelect. Eng. 117, 26–34 (2014)CrossRefGoogle Scholar
  4. 4.
    C. Li, X. Wang, S. Song et al., 21-Layer 3-D chip stacking based on Cu-Sn bump bonding. IEEE Trans. Comp. Pack. Manu. Tech. 5(5), 627–633 (2013)Google Scholar
  5. 5.
    K.N. Tu, H.Y. Hsiao, C. Chen, Transition from flip chip solder joint to 3D IC microbump: its effect on microstructure anisotropy. Microelect. Rel. 53, 2–6 (2013)CrossRefGoogle Scholar
  6. 6.
    S.Y. Huang, T.C. Chang, R.S. Cheng et al., Failure mechanism of 20 μm pitch microjoint within a chip stacking architecture. In 2011 I.E. 61st Electronic Components and Technology Conference (ECTC ), CPMT, Lake Buena Vista, FL, May 31 2011–June 3 2011, p 886
  7. 7.
    W.H. Chen, C.F. Yu, H.C. Cheng et al., IMC growth reaction and its effects on solder joint thermal cycling reliability of 3D chip stacking packaging. Microelec. Rel. 53, 30–40 (2013)CrossRefGoogle Scholar
  8. 8.
    Y.J. Chen, C.K. Chung, C.R. Yang et al., Single-joint shear strength of micro Cu pillar solder bumps with different amounts of intermetallics. Microelec. Rel. 53, 47–52 (2013)CrossRefGoogle Scholar
  9. 9.
    T. Suzuki, K. Asami, Y. Kitamura, T. Fukushima et al., Challenges of high-robustness self-assembly with Cu/Sn-Ag microbump bonding for die-to-wafer 3D integration. In 2015 I.E. 65th Electronic Components and Technology Conference (ECTC ) CPMT, San Diego, 26–29 May 2015, p 312
  10. 10.
    P. Soussan, B. Majeed, P.L. Boterf et al., Evaluation of Sn-based microbumping technology for hybrid IR detectors. 10μm pitch to 5μm pitch, In 2015 I.E. 65th Electronic Components and Technology Conference (ECTC ) ,CPMT, San Diego, 26–29 May 2015, p. 597
  11. 11.
    H.Y. Chen, C.H. Tung, Y.L. Hsiao et al., Electromigration immortality of purely intermetallic micro-bump for 3D integration. In 2015 I.E. 65th Electronic Components and Technology Conference (ECTC ), CPMT, San Diego, 26–29 May 2015, p. 620
  12. 12.
    K.H. Kuo, C. Mao, K. Wang et al., The impact and performance of electromigration on fine pitch Cu pillar with different bump structure for flip chip packaging. In 2015 I.E. 65th Electronic Components and Technology Conference (ECTC ), CPMT, San Diego, 26–29 May 2015, p. 626
  13. 13.
    J.W. Shin, Y.S. Kim, H.G. Lee et al., Effects of thermos-compression bonding parameters on joint formation of micro-bumps in non-conductive film. In 2015 I.E. 65th Electronic Components and Technology Conference (ECTC ), CPMT, San Diego, 26–29 May 2015, p. 910
  14. 14.
    N. Islam, G. Kim, K.O. Kim, Electromigration for advanced Cu interconnect and the challenges with reduced pitch bumps. In 2014 I.E. 64th Electronic Components and Technology Conference (ECTC ) CPMT, Lake Buena Vista, FL, 27–30 May 2014, p. 50
  15. 15.
    K.H. Kuo, J. Lee, F.L. Chien et al., Electromigration performance of Cu pillar bump for flip chip packaging with bump on trace by using thermal compression bonding. In 2014 I.E. 64th Electronic Components and Technology Conference (ECTC ), CPMT, Lake Buena Vista, FL, 27–30 May 2014, p. 56
  16. 16.
    Y. Liu, M. Li, D.W. Kim et al., Filler trap and solder extrusion in 3D IC thermo-compression bonded microbumps. In 2014 I.E. 64th Electronic Components and Technology Conference (ECTC ), CPMT, Lake Buena Vista, FL, 27–30 May 2014, p. 609
  17. 17.
    K. Murayama, M. Aizawa, M. Higashi, Study of electro-migration resistivity of microbump using SnBi solder. In 2014 I.E. 64th Electronic Components and Technology Conference (ECTC ), CPMT, Lake Buena Vista, FL, 27–30 May 2014, p. 1166
  18. 18.
    J. De Vos, L. Bogaerts, T. Buisson et al., Microstructural and morphological characterization of SnAgCu micro-bumps for integration in 3D interconnects. In 2013 I.E. 63rd Electronic Components and Technology Conference CPMT, Las Vegas, NV, 28–31 May 2013, p. 1122
  19. 19.
    J. Bertheau, P. Bleuet, R. Pantel et al., Microstructural and morphological characterization of SnAgCu micro-bumps for Integration in 3D interconnects. In 2013 I.E. 63rd Electronic Components and Technology Conference , CPMT, Lake Buena Vista, FL, 28–31 May 2013, p. 1127
  20. 20.
    B. Dang, S. Wright, J. Maria et al., NiFe-based ball-limiting-metallurge (BLM) for microbumps at 50 um pitch in 3D chip stacks. In 2013 I.E. 63rd Electronic Components and Technology Conference CPMT, Lake Buena Vista, FL, 28–31 May 2013, p 1595
  21. 21.
    H.Y. Son, S.K. Noh, H.H. Jung et al., Reliability studies on micro-bump for 3-D TSV integration. In 2013 I.E. 63rd Electronic Components and Technology Conference ,CPMT, Lake Buena Vista, FL, 28–31 May 2013, p. 29
  22. 22.
    J.Y. Juang, S.Y. Huang, C.J. Zhan et al., Effect of metal finishing fabricated by electro and electro-less plating process on reliability performance of 30 μm-pitch solder microbump interconnection. In 2013 I.E. 63rd Electronic Components and Technology Conference , CPMT, Lake Buena Vista, FL, 28–31 May 2013, p. 653
  23. 23.
    Y. Ito, T. Fukushima, K.W. Lee et al., Flux-assisted self-assembly with microbump bonding for 3D heterogeneous integration. In 2013 I.E. 63rd Electronic Components and Technology Conference , CPMT, Lake Buena Vista, FL, 28–31 May 2013, p. 891
  24. 24.
    Y. Wang, S.H. Chae, J. Im et al., Kinetic study of intermetallic growth and its reliability implications in Pb-free Sn-based microbumps in 3D integration. In 2013 I.E. 63rd Electronic Components and Technology Conference , CPMT, Lake Buena Vista, FL, 28–31 May 2013, p. 1953
  25. 25.
    Y. Wang, S.Y. Chae, R. Dunne et al., Effect of intermetallic formation on electromigration reliability of TSV-microbump joints in 3D interconnect. In 2012 I.E. 62nd Electronic Components and Technology Conference CPMT, San Diego, CA, 29 May 2012–1 June 2012, p. 319
  26. 26.
    C.K. Lee, C.J. Zhan, J.H. Lau et al., Wafer bumping, assembly, and reliability assessment of μbumps with 5μm pads on 10μm pitch for 3D IC integration. In 2012 I.E. 62nd Electronic Components and Technology Conference , CPMT, San Diego, CA, 29 May 2012–1 June 2012, p. 636
  27. 27.
    Y.S. Park, J.W. Shin, Y.W. Choi et al., A study on the intermetallic growth of fine-pitch Cu pillar/SnAg solder bump for 3D-TSV interconnection. In 2012 I.E. 62nd Electronic Components and Technology Conference , CPMT, San Diego, CA, 29 May 2012–1 June 2012, p. 2053
  28. 28.
    R. Dunne, Y. Takahashi, K. Mawatari et al., Development of a stacked WCSP package platform using TSV (through silicon via) technology. In 2012 I.E. 62nd Electronic Components and Technology Conference , CPMT, San Diego, CA, 29 May 2012–1 June 2012, p. 1062
  29. 29.
    Y. Choi, J. Shin, K.W. Paik, 3D-TSV vertical interconnection method using Cu/SnAg double bumps and B-stage non-conductive adhesives (NCAs). In 2012 I.E. 62nd Electronic Components and Technology Conference , CPMT, San Diego, CA, 29 May 2012–1 June 2012, p. 1077
  30. 30.
    Y.M. Lin, C.J. Zhan, J.Y. Juang, J.H. Lau et al., Electromigration in Ni/Sn intermetallic microbump joint for 3D IC chip stacking. In 2011 I.E. 61st Electronic Components and Technology Conference (ECTC ), CPMT, Lake Buena Vista, FL, 31 May 2011–3 June 2011, p. 332
  31. 31.
    A. Syed, K. Dhandapani, R. Moody et al., Cu pillar and μ-bump electromigration reliability and comparison with high Pb, SnPb, and SnAg bumps. In 2011 I.E. 61st Electronic Components and Technology Conference (ECTC ), CPMT, Lake Buena Vista, FL, 31 May 2011–3 June 2011, p. 332
  32. 32.
    W. Zhang, B. Dimcic, P. Limaye et al., Ni/Cu/Sn bumping scheme for fine-pitch micro-bump connections. 2011 I.E. 61st Electronic Components and Technology Conference (ECTC ), CPMT, Lake Buena Vista, FL, 31 May 2011–3 June 2011, p. 109
  33. 33.
    Y. Ito, T. Fukushima, K.W. Lee et al., Reductant-assisted self-assembly with Cu/Sn microbump for three-dimensional heterogeneous integration. Jpn. J. Appl. Phys. 52, 04CB09-1-04CB09-6Google Scholar
  34. 34.
    Y.H. Ko, M.S. Kim, J. Bang et al., Properties and reliability of solder microbump joints between Si chips and a flexible substrate. J. Elect. Mater. 44(7), 2458–2466 (2015)CrossRefGoogle Scholar
  35. 35.
    H.Y. Hsiao, A.D. Trigg, T.C. Chai, Failure mechanism for fine pitch microbump in Cu/Sn/Cu system during current stressing. IEEE Trans. Comp. Pack. Manufact. Tech. 5(3), 314–319 (2015)CrossRefGoogle Scholar
  36. 36.
    M. Hansen, K. Anderko, Constitution of Binary Alloys, 2nd edn. (McGraw-Hill, New York, 1985)Google Scholar
  37. 37.
    H.Y. You, Y.S. Lee, S.K. Lee et al., Reliability of 20μm microbump interconnects. In 2011 I.E. 61st Electronic Components and Technology Conference (ECTC ), CPMT, Lake Buena Vista, FL, 31 May 2011–3 June 2011, p. 608
  38. 38.
    E.A. Brandes (ed.), Smithells Metals Reference Book (Butterworths, London, 1983)Google Scholar
  39. 39.
    K. Hoshino, Y. Iijima, K. Hirano, Interdiffusion and Kirkendall effect in Cu-Sn alloys. Trans. Jpn. Inst. Met. 21(10), 674–682 (1980)CrossRefGoogle Scholar
  40. 40.
    B.F. Dyson, T.R. Anthony, D. Turnbull, Interstitial diffusion of copper in tin. J. Appl. Phys. 38, 3408 (1967)CrossRefGoogle Scholar
  41. 41.
    D.C. Yeh, H.B. Huntington, Extreme fast-diffusion system: nickel in single-crystal tin. Phys. Rev. Lett. 53, 1469–1472 (1984)CrossRefGoogle Scholar
  42. 42.
    Y. Wang, I.M. De Rosa, K.N. Tu, Size effect on ductile-to-brittle transition in Cu-solder-Cu micro-joints. In 2015 I.E. 65th Electronic Components and Technology Conference (ECTC ), CPMT, Lake Buena Vista, FL, 26–29 May 2015, p. 632
  43. 43.
    W.L. Chiu, C.M. Liu, Y.S. Haung et al., Formation of nearly void-free Cu3Sn intermetallic joints using nanotwinned Cu metallization. Appl. Phys. Lett. 104, 171902 (2014)CrossRefGoogle Scholar
  44. 44.
    H.Y. Hsiao, C.M. Liu, H.W. Lin et al., Unidirectional growth of microbumps on (111)-oriented and nanotwinned copper. Science 336, 1007–1010 (2012)CrossRefGoogle Scholar
  45. 45.
    Y.H. Hsiao, K.L. Lin, The formation and conversion of intermetallic compounds in the Cu pillar Sn-Ag micro-bump with ENEPIG Cu substrate under current stressing. J. Mat. Sci Mat. Elect. 27, 2201–2205 (2016).Google Scholar

Copyright information

© Springer International Publishing Switzerland 2017

Authors and Affiliations

  1. 1.Department of Materials Science and EngineeringNational Cheng Kung UniversityTainanTaiwan

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