Journal of Electronic Materials

, Volume 39, Issue 1, pp 124–131 | Cite as

Growth of Intermetallic Compounds in Thermosonic Copper Wire Bonding on Aluminum Metallization

  • Hui Xu
  • Changqing Liu
  • Vadim V. Silberschmidt
  • Zhong Chen


Interface evolution caused by thermal aging under different temperatures and durations was investigated by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found that approximately 30-nm-thick and discontinuous Cu-Al intermetallic compounds (IMCs) were present in the initial bonds before aging. Cu-Al IMCs grew under thermal aging with increasing aging time. The growth kinetics of the Cu-Al IMCs was correlated to the diffusion process during aging; their combined activation energy was estimated to be 1.01 eV. Initially, Al-rich Cu-Al IMCs formed in the as-bonded state and early stage of aging treatment. Cu9Al4 was identified by selected-area electron diffraction (SAD) as the only type of Cu-Al IMC present after thermal aging at 250°C for 100 h; this is attributed to the relatively short supply of aluminum to the interfacial reaction.


Copper wire bonding interfacial analysis intermetallic compounds growth kinetics bonding mechanism 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.



This paper is an output of the PMI2 Project funded by the UK Department for Innovation, Universities, and Skills (DIUS) for the benefit of the Singapore Higher Education Sector and the UK Higher Education Sector. Authors would also like to acknowledge Dr. Geoff West, Mr. John Bates, and Mr. Honghui Wang for their assistance with experiments.


  1. 1.
    G.G. Harman, Wire Bonding in Microelectronics, Materials, Processes, Reliability, and Yield, 2nd ed. (New York: McGraw-Hill, 1997).Google Scholar
  2. 2.
    E. Philofsky, Solid State Electron. 13, 1391 (1970).CrossRefADSGoogle Scholar
  3. 3.
    G.Y. Jang, J.G. Duh, H. Takahashi, and D. Su, J. Electron. Mater. 35, 323 (2006).CrossRefADSGoogle Scholar
  4. 4.
    H. Ji, M. Li, C. Wang, and H.S. Bang, Mater. Sci. Eng. A 447, 111 (2007).CrossRefGoogle Scholar
  5. 5.
    H.S. Chang, J.X. Pon, K.C. Hsieh, and C.C. Chen, J. Electron. Mater. 30, 1171 (2001).CrossRefADSGoogle Scholar
  6. 6.
    S. Murali, J. Alloy Compd. 426, 200 (2006).CrossRefGoogle Scholar
  7. 7.
    S. Murali, N. Srikanth, and C.J. Vath, Mater. Lett. 58, 3096 (2004).CrossRefGoogle Scholar
  8. 8.
    N. Srikanth, S. Murali, Y.M. Wong, and C.J. Vath, Thin Solid Films 462–463, 339 (2004).CrossRefGoogle Scholar
  9. 9.
    S. Murali, N. Srikanth, Y.M. Wong, and C.J. Vath, J. Mater. Sci. 42, 615 (2007).CrossRefADSGoogle Scholar
  10. 10.
    C.D. Breach and F. Wulff, Microelectron. Reliab. 44, 973 (2004).CrossRefGoogle Scholar
  11. 11.
    A. Karpel, G. Gur, Z. Atzmon, and W. Kaplan, J. Mater. Sci. 42, 2334 (2007).CrossRefADSGoogle Scholar
  12. 12.
    P. Ratchev, S. Stoukatch, and B. Swinnen, Microelectron. Reliab. 46, 1315 (2006).CrossRefGoogle Scholar
  13. 13.
    S. Murali, N. Srikanth, and C.J. Vath, Mater. Res. Bull. 38, 637 (2003).CrossRefGoogle Scholar
  14. 14.
    H.J. Kim, J.Y. Lee, K.W. Paik, K.W. Koh, J.H. Won, S.Y. Choe, J. Lee, J.T. Moon, and Y.J. Park, IEEE Trans. Compon. Packag. Technol. 26, 367 (2003).CrossRefGoogle Scholar
  15. 15.
    Y. Funamizu and K. Watanabe, Trans. Jpn. Inst. Met. 12, 147 (1971).Google Scholar
  16. 16.
    Y. Tamou, J. Li, S.W. Russell, and J.W. Mayer, Nucl. Instrum. Methods B 64, 130 (1992).CrossRefADSGoogle Scholar
  17. 17.
    K. Rajan and E.R. Wallach, J. Cryst. Growth 49, 297 (1980).CrossRefADSGoogle Scholar
  18. 18.
    J.P. Lokker, A.J. Böttger, W.G. Sloof, F.D. Tichelaar, G.C.A.M. Janssen, and S. Radelaar, Acta Mater. 49, 1339 (2001).CrossRefGoogle Scholar
  19. 19.
    M. Koberna and J. Fiala, Mater. Sci. Eng. A 159, 231 (1992).CrossRefGoogle Scholar
  20. 20.
    H. Xu, C. Liu, V.V. Silberschmidt, S.S. Pramana, T.J. White, and Z. Chen, Scripta Mater. 61, 165 (2009).CrossRefGoogle Scholar
  21. 21.
    J.R. Ho, C.C. Chen, and C.H. Wang, Sens. Actuators A 111, 188 (2004).CrossRefGoogle Scholar
  22. 22.
    Y.R. Jeng and J.H. Horng, J. Tribol. 123, 725 (2001).CrossRefGoogle Scholar
  23. 23.
    Y. Tanaka, M. Kajihara, and Y. Watanabe, Mater. Sci. Eng. A 445–446, 355 (2007).Google Scholar
  24. 24.
    M. Kajihara, Mater. Sci. Eng. A 403, 234 (2005).CrossRefGoogle Scholar
  25. 25.
    W.B. Lee, K.S. Bang, and S.B. Jung, J. Alloy Compd. 390, 212 (2005).CrossRefGoogle Scholar
  26. 26.
    M. Braunovic and N. Alexandrov, IEEE Trans. Compon. Packag. Manuf. Technol. 17, 78 (1994).CrossRefGoogle Scholar

Copyright information

© TMS 2009

Authors and Affiliations

  • Hui Xu
    • 1
  • Changqing Liu
    • 1
  • Vadim V. Silberschmidt
    • 1
  • Zhong Chen
    • 2
  1. 1.Wolfson School of Mechanical and Manufacturing EngineeringLoughborough UniversityLoughboroughUK
  2. 2.School of Materials Science and EngineeringNanyang Technological UniversitySingaporeSingapore

Personalised recommendations