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International Journal of Fracture

, Volume 185, Issue 1–2, pp 115–127 | Cite as

Temperature, moisture and mode-mixity effects on copper leadframe/EMC interfacial fracture toughness

  • Hai T. Tran
  • M. Hossein Shirangi
  • Xiaolu Pang
  • Alex A. Volinsky
Original Paper

Abstract

A systematic investigation and characterization of the interfacial fracture toughness of the bi-material copper leadframe/epoxy molding compound is presented. Experiments and finite element simulations were used to investigate delamination and interfacial fracture toughness of the bi-material. Two dimensional simulations using virtual crack closure technique, virtual crack extension and J-integral proved to be computationally cheap and accurate to investigate and characterize the interfacial fracture toughness of bi-material structures. The effects of temperature, moisture diffusion and mode-mixity on the interfacial fracture toughness of the bi-material were considered. Testing temperature and moisture exposure significantly reduce the interfacial fracture toughness, and should be avoided if possible.

Keywords

Energy release rate Interfacial fracture toughness  Copper leadframe Epoxy molding compound Delamination  Finite element simulation 

References

  1. Agrawal A, Karlsson AM (2006) Obtaining mode mixity for a bimaterial interface crack using the virtual crack closure technique. Int J Fract 141:75–98CrossRefGoogle Scholar
  2. Anderson TL (2005) Fracture mechanics-fundamentals and applications. CRC Press, Boca Raton, FLGoogle Scholar
  3. Chan EKL, Yuen MMF (2009) Study of interfacial moisture diffusion at epoxy/Cu interface. J Adhesion Sci Technol 23:1253–1269CrossRefGoogle Scholar
  4. Charalambides PG, Lund J, Evans AG, McMeeking RM (1989) A test specimen for determining the fracture resistance of bimaterial interface. J Appl Mech 111:77–82Google Scholar
  5. Fan HB, Chung PWK, Yuen MMF, Chan PCH (2005) An energy-based failure criterion for delamination initiation in electronic packaging. J Adhesion Sci Technol 19:1375–1386CrossRefGoogle Scholar
  6. Hutchinson JW, Suo Z (1992) Mixed mode cracking in layered materials. Adv Appl Mech 29:63–191 Google Scholar
  7. Irwin GR (1957) Analysis of stresses and strains near the end of a crack traversing a plate. J Appl Mech 24:361–364Google Scholar
  8. Jensen HM, Thouless MD (1993) Effects of residual stresses in the blister test. Int J Solids Struct 30:779–795Google Scholar
  9. Komori S, Sakamoto Y (2009) Development trend of epoxy molding compound for encapsulating semiconductor chips. In: Materials for advanced packaging. Springer, Newyork, pp 339–363Google Scholar
  10. Krueger R (2002) The virtual crack closure technique: history, approach and applications. ICASE, Hampton, VAGoogle Scholar
  11. Liechti KM, Chai YS (1991) Biaxial loading experiments for determining interfacial fracture toughness. Trans ASME 58:680–687CrossRefGoogle Scholar
  12. Liechti KM, Chai YS (1992) Asymmetric shielding in interfacial. Fracture under in-plane shear. J Appl Mech 59:295CrossRefGoogle Scholar
  13. Rice JR, Sih GC (1968) Plane problems of cracks in dissimilar media. J Appl Mech 32:418–423CrossRefGoogle Scholar
  14. Shirangi MH, Gollhardt A, Fischer A, Müller WH, Michel B (2008) Investigation of fracture toughness and displacement fields of copper/polymer interface using image correlation technique. In: Proceedings of the 41st international symposium on microelectronics (IMAPS2008), Providence, USAGoogle Scholar
  15. Shirangi HM (2010) Simulation-based Investigation of interface delamination in plastic IC packages under temperature and moisture loading. PhD thesis, Fraunhofer Institute IZM, Berlin, GermanyGoogle Scholar
  16. Swallowe GM (1999) Mechanical properties and testing of polymers. Springer Science and Business Media DordrechtGoogle Scholar
  17. Volinsky AA, Tymiak NI, Kriese MD, Gerberich WW, Hutchinson JW (1999) Quantitative modeling and measurement of copper thin film adhesion. Mat Res Soc Symp Proc 539:277–290CrossRefGoogle Scholar
  18. Wong CKY, Gu H, Xu B, Yuen MMF (2006) A new approach in measuring Cu-EMC adhesion strength by AFM. IEEE Trans Compon Packag Technol 29(3):543–550Google Scholar
  19. Xie W, Sitaraman SK (2003) Investigation of interfacial delamination of a copper-epoxy interface under monotonic and cyclic loading: experimental characterization. IEEE Trans Compon Packag Technol 26(4):447–452Google Scholar

Copyright information

© Springer Science+Business Media Dordrecht 2013

Authors and Affiliations

  • Hai T. Tran
    • 1
  • M. Hossein Shirangi
    • 2
  • Xiaolu Pang
    • 3
  • Alex A. Volinsky
    • 1
  1. 1.Department of Mechanical EngineeringUniversity of South FloridaTampaUSA
  2. 2.Robert Bosch GmbH, Automotive ElectronicsStuttgartGermany
  3. 3.Department of Materials Physics and ChemistryUniversity of Science and Technology BeijingBeijingChina

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