A comparative study on direct Cu–Cu bonding methodologies for copper pillar bumped flip-chips

Article
  • 19 Downloads

Abstract

Copper pillar micro bump is one of the platform technologies, which is essentially required for 2.5D/3D chip stacking and high-density electronic components. In this study, Cu–Cu direct thermo-compression bonding (TCB) and anisotropic conductive paste (ACP) bonding methods are proposed for Ø 100 µm Cu-pillar bumped flip-chips. The process parameters including bonding temperature, bonding pressure and time are verified by die shear test and SEM/EDX cross-sectional analysis. The optimal bonding condition for TCB with regards to bonding pressure was defined to be 0.5N/bump at 300 °C or 0.3N/bump at 360 °C. In the case of ACP bonding, the minimum bonding pressure was about 0.3N/bump for gaining a seamless bonding interface.

Notes

Acknowledgements

This project has been supported by the COMET K1 center ASSIC (Austrian Smart Systems Integration Research Center). The COMET (Competence Centers for Excellent Technologies) Program is supported by BMVIT, BMWFW and the federal provinces of Carinthia and Styria.

References

  1. 1.
    K.W. Lee, 3-D hetero-integration technologies for multifunctional convergence systems. J. Microelectron. Packag. Soc. 22, 11–19 (2015)CrossRefGoogle Scholar
  2. 2.
    M. Gerber, C. Beddingfield, S. O’Connor, M. Yoo, M.J. Lee, D.B. Kang, S.S. Park, C. Zwenger, R. Darveaux, R. Lanzone, K.R. Park, Next generation fine pitch Cu Pillar technology—enabling next generation silicon nodes, Electronic Components and Technology Conference (ECTC), IEEE 61st, pp. 612–618 (2011)Google Scholar
  3. 3.
    K.Y. Au, F.X. Che, J.L. Aw, J.K. Lin, B. Boehme, F. Kuechenmeister, Thermo-compression bonding assembly process and reliabilty studies of Cu pillar bump on Cu/Low-K Chip, Electronic Components and Technology Conference (ECTC), IEEE 16th, pp. 574–578 (2014)Google Scholar
  4. 4.
    C.S. Tan, D.F. Lim, X.F. Ang, J. Wei, K.C. Leong, Low temperature Cu Cu thermo-compression bonding with temporary passivation of self-assembled monolayer and its bond strength enhancement. Microelectron. Reliab. 52, 321–324 (2012)CrossRefGoogle Scholar
  5. 5.
    A. Shigetou, T. Itoh, M. Matsuo, N. Hayasaka, K. Okumura, T. Suga, Bumpless interconnect through ultrafine Cu electrodes by means of surface-activated bonding (SAB) method. IEEE Trans. Adv. Packag. 29(2), 218–226 (2006)CrossRefGoogle Scholar
  6. 6.
    R. He, M. Fujino, M. Akaike, T. Suga, Cu/adhesive hybrid bonding at 180 °C in H-containing HCOOH Vapor ambient for 2.5D/3D integration, Electronic Components and Technology Conference (ECTC), IEEE 67st, pp. 1243–1248 (2017)Google Scholar
  7. 7.
    Y.S. Tang, Y.J. Chen, K.N. Chen, Wafer-level Cu–Cu bonding technology. Microelectron. Reliab. 52, 312–320 (2012)CrossRefGoogle Scholar
  8. 8.
    R.I. Made, P. Lan, H.Y. Li, C.L. Gan, C.S. Tan, Effect of direct current stressing to Cu–Cu bond interface imperfection for three dimensional integrated circuits. Microelectron. Eng. 106, 149–154 (2013)CrossRefGoogle Scholar
  9. 9.
    Z. Zhang, C.P. Wong, Recent advances in flip-chip underfill: materials, process, and reliability. IEEE Trans. Adv. Packag. 27(3), 515–524 (2004)CrossRefGoogle Scholar
  10. 10.
    S.H. Lee, J. Sung, S.E. Kim, Dynamic flow measurements of capillary underfill through a bump array in flip chip package. Microelectron. Reliab. 50, 2078–2083 (2010)CrossRefGoogle Scholar
  11. 11.
    Y.B. Kim, J. Sung, Capillary-driven micro flows for the underfill process in microelectronics packaging. J. Mech. Sci. Technol. 26(12), 3751–3759 (2012)CrossRefGoogle Scholar
  12. 12.
    T.F. Yang, K.S. Kao, R.C. Cheng, J.Y. Chang, C.J. Zhan, Evaluation of Cu/SnAg microbump bonding processes for 3D integration using wafer-level underfill film. Solder. Surf. Mt. Technol. 24, 287–293 (2012)CrossRefGoogle Scholar
  13. 13.
    J.S. Lee, J.K. Kim, M.S. Kim, N. Kang, J.H. Lee, Reliability of flip-chip bonded RFID die using anisotropic conductive paste hybrid material. Trans. Nonferrous Met. Soc. China 21, 175–181 (2011)CrossRefGoogle Scholar
  14. 14.
    M.A. Uddin, M.O. Alam, Y.C. Chan, H.P. Chan, Adhesion strength and contact resistance of flip chip on flex packages-effect of curing degree of anisotropic conductive film. Microelectron. Reliab. 44, 505–514 (2004)CrossRefGoogle Scholar
  15. 15.
    M. Teo, S.G. Mhaisalkar, E.H. Wong, P.S. Teo, C.C. Wong, K. Ong, C.F. Goh, K.L. Teh, Correlation of material properties to reliability performance of anisotropic conductive adhesive flip chip packages. IEEE Trans. Compon. Packag. Technol. 28(1), 157–164 (2005)CrossRefGoogle Scholar
  16. 16.
    J. Fan, C.S. Tan, Low temperature wafer-level metal thermo-compression bonding technology for 3D integration, in Metallurgy—Advances in Materials and Processes, ed. by Y. Pardhi (Intech, Rijeka, 2012)Google Scholar
  17. 17.
    MIL-STD-883E, Test method standard—Microcircuits, USA, (1996)Google Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.CTR Carinthian Tech Research AGVillachAustria

Personalised recommendations