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Mechanism of Moisture Diffusion, Hygroscopic Swelling, and Adhesion Degradation in Epoxy Molding Compounds

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Moisture Sensitivity of Plastic Packages of IC Devices

Abstract

Epoxy molding compounds (EMCs) are widely used as encapsulation materials for protecting the semiconductor chips of plastic encapsulated microcircuits (PEMs) against harsh environments and mechanical forces such as impact and pressure. Since PEMs are usually exposed to humid conditions during their storage and service life, they absorb moisture, which causes many reliability problems such as popcorn cracking and interfacial delamination during the solder reflow process. This chapter presents a comprehensive investigation of the mechanism of moisture diffusion in EMCs. The results from moisture diffusion tests during absorption, desorption, and re-sorption of various EMC samples are presented. The gravimetric results showed a non-Fickian behavior of the moisture diffusion in the EMCs. This non-Fickian behavior was found to induce a non-reversible effect by causing some residual moisture content upon baking these plastic parts. The gravimetric moisture diffusion results can be correlated to moisture-induced hygroscopic swelling and adhesion loss. Hygroscopic swelling of EMC and its reversibility was investigated using both bulk EMC samples and bi-material beams. Moreover, the effect of moisture on the adhesion of EMC/Cu interface was studied using a fracture mechanics approach. Two mechanisms of adhesion loss upon moisture diffusion can be observed. Some of the adhesion loss due to small amount of moisture content may be recovered via a proper annealing. However, upon long-term storage in humid conditions, where the second phase of non-Fickian behavior is activated at the interface, none of the adhesion loss can be recovered after baking the samples.

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References

  1. Shirangi, M.H., Auersperg, J., Koyuncu, M., Walter, H., Müller, W.H., Michel, B., “Characterization of dual-stage moisture diffusion, residual moisture content and hygroscopic swelling of epoxy molding compounds,” Proceedings of the 9th EuroSime2008, Freiburg, Germany, pp. 455–462, 2008.

    Google Scholar 

  2. Shirangi, M.H., Fan, X.J., Michel, B., “Mechanism of moisture diffusion, hygroscopic swelling and adhesion degradation in epoxy molding compounds,” Proceedings of the 41st International Symposium on Microelectronics (IMAPS), Providence, USA, pp. 1082–1089, 2008.

    Google Scholar 

  3. Fan, X.J., Zhou, J., Chandra, A., “Package structural integrity analysis considering moisture,” Proceedings of Electronic Components and Technology Conference (ECTC), Orlando, USA, pp. 1054–1066, 2008.

    Google Scholar 

  4. Pecht, M.G., Nguyen, L.T., Hakim, E.B., Plastic-Encapsulated Microelectronics. New York, NY: Wiley, 1995.

    Google Scholar 

  5. Ardebili, H., Hillman, C., Natishan, M.A.E., McCluskey, P., Pecht, M.G., Peterson, D., “A comparison of the theory of moisture diffusion in plastic encapsulated microelectronics with moisture sensor chip and weight-gain measurements,” IEEE Transaction on Components and Packaging Technologies, 25, 132–139, 2002.

    Article  Google Scholar 

  6. Fan, X.J., Lee, S.W.R., Han, Q., “Experimental investigations and model study of moisture behaviors in polymeric materials”, Microelectronics Reliability, 49, 861–871, 2009.

    Article  Google Scholar 

  7. Fan, X.J., “Mechanics of moisture for polymers: fundamental concepts and model study,” Proceedings of the 9th EuroSime, Freiburg, Germany, pp. 159–172, 2008.

    Google Scholar 

  8. Shirangi, M.H., Müller, W.H., Michel, B., “Determination of Copper/EMC interface fracture toughness during manufacturing, moisture preconditioning and solder reflow process of semiconductor packages,” Proceedings of International Conference on Fracture (ICF12), Ottawa, Canada, 2009.

    Google Scholar 

  9. Teverovsky, A., Moisture Characteristics of Molding Compounds in PEMs, Lanham, MD: QSS Group, Inc./Goddard Operations.

    Google Scholar 

  10. Soles, C., Yee A, “A discussion of the molecular mechanisms of moisture transport in epoxy resins,” Journal of Polymer Science, Part B: Polymer Physics, 38, 792–802, 2000.

    Article  Google Scholar 

  11. Adamson, M.J., “Thermal expansion and swelling of cured epoxy resin used in graphite/epoxy composite materials,” Journal of Material Science, 15, 1736–1745, 1980.

    Article  Google Scholar 

  12. Tencer, M.,“Moisture ingress into nonhermetic enclosures and packages – a quasisteady state model for diffusion and attenuation of ambient humidity variations,” IEEE 44th Electronic Components Technology Conference, Washington DC, USA, 1994.

    Google Scholar 

  13. Wong, E.H., Teo, Y.C., Lim, T.B., “Moisture diffusion and vapor pressure modeling of IC packaging,” Proceedings of Electronic Components Technology Conference (ECTC), Seattle, USA, pp. 1372–1378, 1998.

    Google Scholar 

  14. Xie, B., Fan, X.J., Shi, X.Q., Ding, H., “Direct concentration approach of moisture diffusion and whole field vapor pressure modeling for reflow process: part I – theory and implementation”, ASME Journal of Electronic Packaging, 31(3), 031010, 2009.

    Article  Google Scholar 

  15. Vine, K., Cawley, P., Kinloch, A.J., “The correlation of non-destructive measurements and toughness changes in adhesive joints during environmental attack,” Journal of Adhesion, 77, 125–161, 2001.

    Article  Google Scholar 

  16. Davis, D., Krebs, A., Drzal, L.T., Rich, M.J., Askeland, P., “Electrochemical sensors for nondestructive evaluation of adhesive bonds,” Journal of Adhesion, 72, 335–358, 2000.

    Article  Google Scholar 

  17. Zanni-Defarges, M.P., Shanaham, M.E.R., “Evaluation of adhesive shear modulus in a torsional joint: influence of aging,” International Journal of Adhesion and Adhesives, 13, 41–45, 1993.

    Article  Google Scholar 

  18. Chan, E., Yuen, M., “Study of interfacial moisture diffusion at Cu/Epoxy interface by FTIR-MIR technique,” Proceedings of Electronic and Component and Technology Conference, Reno, Nevada; USA, pp. 1782–1787, 2007.

    Google Scholar 

  19. Fan, X.J., “Moisture related reliability in electronic packaging”, Electronic Component Technology Conference (ECTC), Short Course Notes; 2008.

    Google Scholar 

  20. Buchwalter, L.P., “Polyimides: fundamental aspects and applications,” Adhesion of Polyimides to Various Substrates. New York, NY: Marcel Dekker, pp. 587–628, 1996.

    Google Scholar 

  21. O’Brien, E. P., “Durability of adhesive joints subjected to environmental stress,” Dissertation for Doctor of Philosophy. Blacksburg, VA: Virginia Polytechnic Institute, 2003.

    Google Scholar 

  22. Wu, W.L., Orts, W.J., Majkzak, C.J. “Water absorption at a polyimide/silicon wafer interface,” Polymer Engineering & Science, 12, 1000–1004, 1995.

    Google Scholar 

  23. Nguyen, T., Byrd, B., Alsheh, D., McDonough, W., Seiler, J., “Interfacial water and adhesion loss of polymer coatings on a siliceous substrate,” Materials Research Society, 385, 57–63, 1995.

    Google Scholar 

  24. Bowden, F.P., Throssell, W.R., “Adsorption of water vapour on solid surfaces,” Nature, 167, 601–602 April 1951.

    Article  Google Scholar 

  25. Takahashi, M.K., “AC impedance measurements of moisture in interfaces between epoxy and oxidized silicon,” Journal of Applied Physics, 67, 3419, 1990.

    Article  Google Scholar 

  26. Shen, C.H., Springer, G.S., “Moisture absorption and desorption of composite materials,” Journal of Composite Materials, 10, 2–20, 1976.

    Article  Google Scholar 

  27. Chen, X., Zhao, S., “Moisture absorption and diffusion characterization of molding compound,” Journal of Electronic Packaging, 127, 460–465, 2005.

    Article  Google Scholar 

  28. Celik, E., Guven, I., Madenci, E., “Experimental and numerical characterization of non-Fickian moisture diffusion in electronic packages,” Proceedings of Electronic Components and Technology Conference, Reno, Nevada; USA, pp. 1069–1073, 2007.

    Google Scholar 

  29. Weitsman, Y.J., “Anomalous fluid sorption in polymeric composites and its relation to fluid induces damage,” Journal of Composites Part A: Applied Science and Manufacturing, 37, 617–623, 2006.

    Article  Google Scholar 

  30. Loh, W.K., Crocombe, A.D., Abdel Wahab, M.M., Aschroft, I.A., “Modelling anomalous moisture uptake, swelling and thermal characteristics of a rubber toughened epoxy adhesive,” International Journal of Adhesion & Adhesives, 25, 1–12, 2005.

    Article  Google Scholar 

  31. Lekatou, A., Faidi, S.E., Ghidaoui, D., Lyon, S.B., Newman, R.C., “Effect of water and its activity on transport properties of glass/epoxy particulate composites,” Journal of Composites Part A: Applied Science and Manufacturing, 28, 223–236, 1997.

    Article  Google Scholar 

  32. He, Y., Fan, X.J., “In-situ characterization of moisture absorption and desorption in thin BT core substrate,” Proceedings of Electronic Components and Technology Conference, Reno, Nevada; USA, pp. 1375–1383, 2007.

    Google Scholar 

  33. Teverovsky, A., “A rapid technique for moisture diffusion characterization of molding compounds in PEMs,” NEPP Report, GSFC, 2002.

    Google Scholar 

  34. Teverovsky, A., Moisture Characteristics of Molding Compounds in PEMs. Lanham, MD: QSS Group, Inc./Goddard Operations, NASA Technical Report, 2002.

    Google Scholar 

  35. Lin, Y.C., “Investigation of the moisture-desorption characteristics of epoxy resin,” Journal of Polymer Research, 13, 369–374, 2006.

    Article  Google Scholar 

  36. Xie, B., Fan, X.J., Shi, X.Q., Han, D., “Direct concentration approach of moisture diffusion and whole field vapor pressure modeling for reflow process: part II – application to 3-D ultra-thin stacked-die chip scale packages,” ASME Journal of Electronic Packaging, 31(3), 031011, 2009.

    Article  Google Scholar 

  37. Fan, X.J., Zhou, J., Zhang, G.Q., Ernst, L.J., “A micromechanics based vapor pressure model in electronic packages,” ASME Journal of Electronic Packaging, 127(3), 262–267,1 2005.

    Article  Google Scholar 

  38. Ardebili, H., Wong, E.H., Pecht, M., “Hygroscopic swelling and sorption characteristics of epoxy molding compounds used in electronic packaging,” IEEE Transactions on Components and Packaging Technologies, 26, 206–214, 2003.

    Article  Google Scholar 

  39. Shi, X., Zhang, Y., Zhou, W., Fan, X.J., “Effect of hygrothermal aging on interfacial reliability of silicon/underfill/FR-4 assembly,” IEEE Transactions on Components and Packaging Technologies, 31, 94–103, 2008.

    Article  Google Scholar 

  40. Stellrecht, E., Han, B., Pecht, M.G., “Characterization of hygroscopic swelling of mold compounds and plastic packages,” IEEE Transactions on Components and Packaging Technologies, 27, 499–506, 2004.

    Article  Google Scholar 

  41. Zhou, J., Lahoti, S., Kallolimath, K., “Investigation of non-uniform moisture distribution on determination of hygroscopic swelling coefficient and finite element modelling for a flip chip package,” Proceedings of EuroSimE, Berlin, Germany, 2005.

    Google Scholar 

  42. Shirangi, M.H., Müller, W.H., Michel, B., “Effect of nonlinear hygro-thermal and residual stresses on interfacial fracture in plastic IC packages”, Proceedings of the 59th Electronic Components and Technology Conference (ECTC), San Diego, CA, USA, pp. 232–238, 2009.

    Google Scholar 

  43. Shirangi, M.H., Wunderle, B., Wittler, O., Walter, H., Michel, B., “Modeling cure shrinkage and viscoelasticity to enhance the numerical methods for predicting delamination in semiconductor packages,” Proceedings of the 10th EuroSime2009, Delft, The Netherlands, 2009.

    Google Scholar 

  44. Zhou, J., “Sequentially-coupled finite element transient analysis with hygroscopic swelling,” Proceedings of the 7th EuroSimE, Como, Italy, 2006.

    Google Scholar 

  45. Fan, X.J., Zhou, J., Zhang, G.Q., “Multi-physics modeling in virtual prototyping of electronic packages – combined thermal, thermo-mechanical and vapor pressure modeling,” Microelectronics Reliability, 44, 1967–1976, 2004.

    Article  Google Scholar 

  46. Fan, X.J., Zhang, G.Q., van Driel, W.D., Ernst, L.J., “Interfacial delamination mechanisms during reflow with moisture preconditioning,” IEEE Transactions on Components and Packaging Technologies, 31(2), 252–259, 2008.

    Article  Google Scholar 

  47. Dudek, R., Walter, H., Michel, B., “Studies on moisture diffusion and popcorn cracking,” Proceedings of the 3rd EuroSimE, Paris, France, pp. 225–232, 2002.

    Google Scholar 

  48. Ferguson, T., “Moisture and interfacial adhesion in microelectronic assemblies,” Dissertation for the Degree of Doctor of Philosophy. Atlanta, GA: Georgia Institute of Technology, June 2004.

    Google Scholar 

  49. Ferguson, T., Qu, J., “Elastic modulus variation due to moisture absorption and permanent changes upon redrying in an epoxy based underfill,” IEEE Transactions on Components and Packaging Technologies, 29, 105–111, 2005.

    Google Scholar 

  50. Brewis, D.M., Comyn, J., Raval, A.K., Kinloch, A.J., “The effect of humidity on the durability of aluminum-epoxide joints,” International Journal of Adhesion and Adhesive, 10, 247–253, 1990.

    Article  Google Scholar 

  51. Lefebvre, D.R., Elliker, P.R., Takahashi, K.M., Raju, V.R., Kaplan, M.L., “The critical humidity effect in the adhesion of epoxy to glass: role of hydrogen bonding,” Journal of Adhesion Science and Technology, 14(7), 925–937, 2000.

    Article  Google Scholar 

  52. McBrierty, V.J., Martin, S.J., Karasz, F.E., “Understanding hydrated polymers: the perspective of NMR,” Journal of Molecular Liquids, 80(2), 179–205, 1999.

    Google Scholar 

  53. Comyn, J, Groves, C., Saville, R., “Durability in high humidity of glass-to-lead alloy joints bonded with an epoxide adhesive,” International Journal of Adhesion and Adhesives, 14, 15–20, 1994.

    Article  Google Scholar 

  54. Lu, X., Hofstra, P., Bajkar, R., “Moisture absorption, dielectric relaxation, and thermal conductivity studies of polymer composites,” Journal of Polymer Science: Part B: Polymer Physics, 36, 2259–2265, 1998.

    Article  Google Scholar 

  55. Asao, N., Isao, H., Naotaka, T., “A new method for measuring adhesion strength of IC molding compounds,” Journal of Electronic Packaging, 114, 402–412, 1992.

    Google Scholar 

  56. Shirangi, M.H., Gollhardt, A., Fischer, A., Müller, W.H., Michel, B., “Investigation of fracture toughness and displacement fields of copper/polymer interface using image correlation technique,” Proceedings of the 41st International Symposium on Microelectronics (IMAPS), Providence, USA, pp. 917–923, 2008.

    Google Scholar 

  57. Dodiuk, H., Dori, L., Miller, J., “The effect of moisture in epoxy film adhesives on their performance: I. Lap shear strength,” Journal of Adhesion, 17, 33–44, 1984.

    Article  Google Scholar 

  58. Kinloch, A., “Interfacial fracture mechanical aspects of adhesive bonded joints – a review,” Journal of Adhesion, 10, 193–219, 1979.

    Article  Google Scholar 

  59. Lin, Y., Tsui, T.Y., Vlassak, J., “Water diffusion and fracture in organosilicate glass film stacks,” Acta Materialia, 55, 2455–2464, 2007.

    Article  Google Scholar 

  60. Shaw, G., Rogers, V., Payer, J., “The effect of immersion on the breaking force and failure locus in an epoxy/mild steel system,” Journal of Adhesion, 38, 225–268, 1992.

    Article  Google Scholar 

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Shirangi, M.H., Michel, B. (2010). Mechanism of Moisture Diffusion, Hygroscopic Swelling, and Adhesion Degradation in Epoxy Molding Compounds. In: Fan, X., Suhir, E. (eds) Moisture Sensitivity of Plastic Packages of IC Devices. Micro- and Opto-Electronic Materials, Structures, and Systems. Springer, Boston, MA. https://doi.org/10.1007/978-1-4419-5719-1_2

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  • DOI: https://doi.org/10.1007/978-1-4419-5719-1_2

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