Abstract
Current stressing at densities from 2.9 to 7.3 × 104 A/cm2 has significant effects on the atomic migration of eutectic SnBi solder alloys. At lower density (2.9 × 104 A/cm2), electromigration dominates the migration of both Sn and Bi, and drives Sn and Bi atoms to migrate toward the anode side. While at higher densities (4.4 and 7.3 × 104 A/cm2), the enhanced Bi electromigration induces a back stress, which promotes a reversed migration of Sn toward the cathode side. A large number of Sn atoms accumulate at the cathode side and form lumps there.
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References
S. Brandenburg S. Yeh: Electromigration studies of flip chip bump solder joints in Proceedings of the Surface Mount International Conference and Exhibition, SM198, San Jose, CA (SMTA, Edina, MN, 1998), p. 337
C.Y. Liu, C. Chen K.N. Tu: Electromigration in Sn-Pb solder stripes as a function of alloy composition. J. Appl. Phys. 88, 5703 2000
E.C.C. Yeh, W.J. Choi, K.N. Tu, P. Elenius H. Balkan: Current-crowding-induced electromigration failure in flip chip solder joints. Appl. Phys. Lett. 80, 580 2002
S.W. Chen, C.M. Chen W.C. Liu: The electric current effects upon the SnCu and SnNi interfacial reactions. J. Electron. Mater. 27, 1193 1998
Y.C. Hu, Y.H. Lin, C.R. Kao K.N. Tu: Electromigration failure in flip chip solder joints due to rapid dissolution of copper. J. Mater. Res. 18, 2544 2003
G.A. Rinne: Issues in accelerated electromigration of solder bumps. Microelectron. Reliab. 43, 1975 2003
Q.L. Yang J.K. Shang: Interfacial segregation of Bi during current stressing of Sn-Bi/Cu solder interconnect. J. Electron. Mater. 34, 1363 2005
L.T. Chen C.M. Chen: Electromigration study in the eutectic SnBi solder joint on the Ni/Au metallization. J. Mater. Res. 21, 962 2006
C.M. Chen, L.T. Chen Y.S. Lin: Electromigration-induced Bi segregation in eutectic SnBi solder joint. J. Electron. Mater. 36, 168 2007
C.M. Chen, C.C. Huang, C.N. Liao K.M. Liou: Effects of copper doping on microstructural evolution in eutectic SnBi solder stripes under annealing and current stressing. J. Electron. Mater. 36, 760 2007
X.F. Zhang, J.D. Guo J.K. Shang: Abnormal polarity effect of electromigration on intermetallic compound formation in Sn–9Zn solder interconnect. Scripta Mater. 57, 513 2007
H.B. Huntington: Electromigration in metals in Diffusion in Solids: Recent Developments edited by A.S. Nowick and J.J. Burton Academic Press New York 1975 303–352
F. Hua, Z. Mei J. Glazer: Eutectic Sn-Bi as an alternative to Pb-free solders in Proceedings of the 48th Electronic Components and Technology Conference IEEE New York 1998 277
C. Herring: Diffusional viscosity of a polycrystalline solid. J. Appl. Phys. 21, 437 1950
I.A. Blech: Electromigration in thin aluminum films on titanium nitride. J. Appl. Phys. 47, 1203 1976
I.A. Blech: Diffusional back flows during electromigration. Acta Mater. 46, 3717 1998
H.C. Yu, S.H. Liu C. Chen: Study of electromigration in thin tin film using edge displacement method. J. Appl. Phys. 98, 013540 2005
C.C. Wei C. Chen: Critical length of electromigration for eutectic SnPb solder stripe. Appl. Phys. Lett. 88, 182105 2006
Acknowledgments
The authors wish to acknowledge the financial support of the National Science Council of Taiwan, Republic of China, through Grant No. NSC 95-2221-E-005-143. This work is supported in part by the Ministry of Education, Taiwan, Republic of China, under the ATU plan.
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Chen, Cm., Huang, Cc. Atomic migration in eutectic SnBi solder alloys due to current stressing. Journal of Materials Research 23, 1051–1056 (2008). https://doi.org/10.1557/jmr.2008.0128
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DOI: https://doi.org/10.1557/jmr.2008.0128