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Cyclic Stress-Strain Behavior of BGA (Sn/3.5Ag/0.75Cu) Solder Joint under Cyclically Oblique Displacement Tests and Endochronic Viscoplastic Predictions

Published online by Cambridge University Press:  28 September 2011

C. F. Lee ,
T. K. Lee ,
T. T. Lin  and
H. Y. Lin
C. F. Lee*
Affiliation:
Department of Eng. Science, College of Eng., National Cheng Kung University, Tainan, Taiwan70101, R.O.C.
T. K. Lee*
Affiliation:
Department of Eng. Science, College of Eng., National Cheng Kung University, Tainan, Taiwan70101, R.O.C.
T. T. Lin*
Affiliation:
Department of Eng. Science, College of Eng., National Cheng Kung University, Tainan, Taiwan70101, R.O.C.
H. Y. Lin*
Affiliation:
CF Inspection Department, CHIMEI, Tainan, Taiwan74144, R.O.C..
*
* Professor, corresponding author
*** Graduate student
*** Graduate student
** Engineer
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Abstract

In this paper, a methodology with workable procedures was proposed and successfully transferred the hysteresis loops of BGA solder joint specimen held by loading-directionally aligned grip system under oblique displacement controlled cyclic tests, into hysteresis loops of “representative” solder ball itself under proportional straining and constant strain rate cyclic tests. Under the elastic unloading during cyclic test, value of elastic modulus of bulk solder specimens and the linear behavior of grip system were used. Following the study of Endochronic cyclic viscoplasticity, the kernel function ρ(Z) = ρ0 exp (−KZ)/Zα was found to be independent of the oblique angle (Φ) of straining paths. However, the steady cyclic behavior of material function f(ξ) ≡ f0 in the definition of intrinsic time Z contained two functions: (1) is the effective inelastic strain amplitude, and (2) f(Φ) Φ(rad) between Φ = 0 (uniaxial) and Φ = π/2 (shear). With (ρ0, α, K) = (4MPa, 0.84, 46) and f0 = [0.24(π/2−Φ)2 − 0.018(π2−Φ) + 1.2] , the endochronic theory predicted experimental hysteresis loops of BGA Sn/3.5Ag/0.75Cu solder joint specimens and Φ = 0°, 27°, 45°, 63°, 90° quite well.

Results of ρ(Z) under f0 = 1 were found under independent study based on cyclic tests of bulk specimens under constant uniaxially strain amplitude and various constant strain rates. The values of (ρ0, α, K) = (7.3MPa, 0.84, 30) with f0 = 1.0 were all independent of strain rates. Comparisons of results of both types of specimens revealed that the values of (α, K) were almost the same but (1) ρ0 was smaller for micro-size solder ball, (2) is a material function of Sn/3.5Ag/0.75Cu itself (3) f(Φ) is not a material function, rather it is a special feature to reflect the effects of detail design of solder joint specimen and its connecting methods to the substrates

Keywords

BGA Sn/3.5Ag/0.75Cu solder joint specimenLoading-directionally aligned grip systemHysteresis loops of testing system under oblique displacement cyclic testHysteresis loops of representative solder ball under proportional straining pathEndochronic cyclic viscoplasticity
Type
Research Article
Information
Journal of Mechanics , Volume 26 , Issue 4 , December 2010 , pp. 453 - 463
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2010

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References

REFERENCES

1. Lau, J. H., Low Cost Flip Chip Technologies for DCA, WLCSP, and PBGA Assemblies, McGraw-Hill Comp. New York (2000).Google Scholar
2. Lau, J. H. and Lee, S. W. R., Chip Scale Package: Design, Materials, Process, Reliability, and Applications, McGraw-Hill Comp. New York (1999).Google Scholar
3. Yeh, C. L. and Lai, Y. S., “Design Guideline for Ball Impact Test Apparatus,” Journal of Electronic Packaging, Trans, ASME, 129, pp. 98–104 (2007).CrossRefGoogle Scholar
4. Shi, X. Q., Pang, H. L. J., Zhou, W. and Wang, Z. P., “Low Cycle Fatigue Analysis of Temperature and Frequency Effects in Eutectic Solder Alloy,” International Journal of Fatigue, 22, pp. 217–228 (2000).CrossRefGoogle Scholar
5. Lee, W. W., Nguyen, L. T. and Selvaduray, G. S., “Solder Joint Fatigue Models: Review and Applicability to Chip Scale Packages,” Microelectronics Reliability, 40, pp. 237–244 (2000).CrossRefGoogle Scholar
6. Chen, X., Jin, D., SaKane, M. and Yamamoto, T., “Multiaxial Low-Cycle Fatigue of 63Sn-37Pb Solder,” Journal of Electronic Materials, 34, pp. L.1–L.6 (2005).CrossRefGoogle Scholar
7. Park, T. S. and Lee, S-B., “Mechanical Fatigue Tests of Solder Joint under Mixed-Mode Loading Cases,” 2001 Int'1 Sym. Electronic Materials and Packaging, (C) 2001 IEEE, pp. 438–443 (2001).Google Scholar
8. Park, T. S. and Lee, S-B., “Isothermal Low-Cycle Fatigue Tests of Sn/3.5Ag/0.75Cu and 63Sn/37Pb Solder Joints under Mixed-Mode Loading Cases,” 2002 Elec-tronic Components and Technology Conference, IEEE, pp. 979–984 (2002).Google Scholar
9. Park, T. S. and Lee, S. B., “Cyclic Stress-Strain Meas-urement Tests of Sn 3.5Ag 0.75Cu Solder Joint,” 2002 Int'1 Sym. Electronic Materials and Packaging, (C) 2002 IEEE, pp. 317–323 (2002).Google Scholar
10. Park, T. S. and Lee, S. B., “Low Cycle Fatigue Testing of Ball Grid Array Solder Joints under Mixed-Mode Loading Conditions,” Journal of Electronic Packaging, ASME, 127, pp. 237–244 (2005).CrossRefGoogle Scholar
11. Lee, C. F. and Shieh, T. J., “Theory of Endochronic Cyclic Viscoplasticity of Eutectic Tin/Lead Solder Alloy,” Journal of Mechanics, 22, pp. 181–191 (2006).CrossRefGoogle Scholar
12. Lee, C. F. and Chen, Y. C., “Thermodynamic Formulation of Endochronic Cyclic Viscoplasticity with Damage Application to Eutectic Sn/Pb Solder Alloy,” Journal of Mechanics, 23, pp. 443–444 (2007).CrossRefGoogle Scholar
13. Lee, C. F. and Lee, Z. H., “Predicting Fatigue Initiation Life of Sn/3.8Ag/0.7Cu Solder using Endochronic Cyclic Damage-Coupled Viscoplastic Theory,” Journal of Mechanics, 24, pp. 369–377 (2008).CrossRefGoogle Scholar
14. Ohguchi, K., Sasaki, K., Ishibashi, M. and Hoshino, T., “Plasticity-Creep Separation Method for Viscoplastic Deformation of Lead-Free Solders,” JSME, Series A, 47, pp. 371–379 (2004).Google Scholar