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A Study of Impact Reliability of Lead-free BGA Balls on Au/Electrolytic Ni/Cu Bond Pad

  • Shengquan Ou (a1), Yuhuan Xu (a1), K. N. Tu (a1), M. O. Alam (a2) and Y. C. Chan (a2)...

Abstract

The most frequent failure of wireless, handheld, and movable consumer electronic products is an accidental drop to the ground. The impact may cause interfacial fracture of wire-bonds or solder joints between a Si chip and its packaging module. Existing metrologies, such as ball shear, and pull test cannot well represent the shock reliability of the package. In this study, a micro-impact machine is utilized to test the impact reliability of three kinds of lead-free solders: 99Sn1Ag, 98.5Sn1Ag0.5Cu and 97.5Sn1Ag0.5Cu1In (hereafter called Sn1Ag, Sn1Ag0.5Cu, and Sn1Ag0.5Cu1In). The effect of thermal aging on the impact toughness is also evaluated in this study. We find a ductile-to-brittle transition in SnAg (Cu) solder joints after thermal aging. The impact toughness is enhanced by the thermal aging. This is a combination effect of the growth of intermetallic compound (IMC) at the interface provided strong bonding, and the softening of the solder bulk during the thermal aging absorbed more energy during plastic deformation.

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1. Mishiro, Kinukoet al, “Effect of the drop impact on BGA/CSP package reliability,” Microelectronics Reliability, 42 (2002), pp. 7782.
2. Nishiura, M, Nakayama, A, Sakatani, S, Kohara, Y, Uenishi, K, KF, Kobayashi, “Mechanical strength and microstructure of BGA joints using lead-free solders,” Mater Trans., 43 (2002), pp. 1802.
3. Chiu, Tz-Cheng, Zeng, Kejun, Stierman, Roger and Edwards, Darvin, Ano, Kazuaki, “Effect of Thermal Aging on Board Level Drop Reliability for Pb-free BGA Packages,” The proceedings of the 54th ECTC, Las Vegas, NV, 2004, pp.1256.
4. Shoji, T, Yamamoto, K, Kajiwara, R, Morita, T, Sato, K, Date, M., Proceedings of the 16th JIEP Annual Meeting, 2002, pp.97.
5. Date, M., Shoji, T., Fujiyoshi, M., Sato, K., and Tu, K. N., “Ductile-to-brittle transition in Sn-Zn solder joints measured by impact test,” Scripta Materialia, 51 (2004), pp.641.
6. Holt, John M., editor, “Charpy Impact Test: Factors and Variables” ASTM STP 1072, Philadelphia, PA, (1990).
7. Zeng, K. and Tu, K. N., “Six cases of reliability study of Pb-free solder joints in electronic packaging technology,” Mater. Sci. Eng., R., 38 (2002), pp. 55.
8. Alam, M. O., Chan, Y. C., and Tu, K. N., “Effect of 0.5 wt.% Cu addition in the Sn-3.5% Ag solder on the interfacial reaction with Au/Ni metallization,” Chemistry of Materials, 15 (2003), pp.43404342.

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A Study of Impact Reliability of Lead-free BGA Balls on Au/Electrolytic Ni/Cu Bond Pad

  • Shengquan Ou (a1), Yuhuan Xu (a1), K. N. Tu (a1), M. O. Alam (a2) and Y. C. Chan (a2)...

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