Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-24T03:04:26.905Z Has data issue: false hasContentIssue false
  • English
  • Français

Effects of Zn addition on the drop reliability of Sn–3.5Ag–xZn/Ni(P) solder joints

Published online by Cambridge University Press:  31 January 2011

Y.K. Jee ,
Jin Yu  and
Y.H. Ko
Y.K. Jee*
Affiliation:
Department of Material Science and Engineering, Korea Advanced Institute of Science and Engineering, Yuseong-gu, Daejeon 305-701, Korea
Jin Yu
Affiliation:
Department of Material Science and Engineering, Korea Advanced Institute of Science and Engineering, Yuseong-gu, Daejeon 305-701, Korea
Y.H. Ko
Affiliation:
Samsung Electronics, Hwasung-city, Gyeongii-do 445-701, Korea
*
a)Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

Varying amounts of Zn (1, 3, 7 wt%) were added to Sn–3.5Ag solder on the electroless Ni(P)/immersion Au metallization, and solder joint microstructures after reflow and isothermal aging (500 h at 150 °C) were investigated using scanning electron microscopy, energy dispersive x-ray spectroscopy, transmission electron microscopy, and x-ray diffraction, which were subsequently correlated to the microhardness and drop test results. Zinc in the solder affected the solder joint intermetallic compounds profoundly, which improved the drop reliability significantly. The effect of Zn was to nucleate Ni5Zn21 and to suppress the formation of Ni3P, Ni3SnP, and Ni3Sn4, which were known to increase the propensity for brittle cracking. Drop test results showed an inverse correlation between the number of drops-to-failure (Nf) and the thickness of Ni3P layer. As the growth of the Ni3P layer was suppressed by Zn, drop reliability increased substantially.

Keywords

Chemical reactionFractureMicrostructure
Type
Articles
Information
Journal of Materials Research , Volume 22 , Issue 10 , October 2007 , pp. 2776 - 2784
Copyright
Copyright © Materials Research Society 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1Eijim, T.I., Hollesen, D.B., Holliday, A., Gahr, S.A.Coyle, R.J.: Assembly and reliability of thermally enhanced high I/O BGA packages in Proc. 21st IEEE International Electronics Manufacturing Symposium,25 (1997)Google Scholar
2Mei, Z., Kauffmann, M., Eslambolchi, A.Johnson, P.: Brittle interfacial fracture of PBGA packages on electroless Ni/immersion Au in Proc. 48th Electronic Component and Technology Conference,952 (1998)Google Scholar
3Biunno, N.: A root cause failure mechanism for solder joint integrity of electroless Ni/immersion gold surface finishes. Proc. IPC Printed Circuit Expo. 1999, s18 1999Google Scholar
4Goyal, D., Lane, T., Kinzie, P., Panichas, C., Chong, K.M.Villalobos, O.: Failure mechanism of brittle solder joint fracture in the presence of electroless nickel/immersion gold surface finishe in Proc. 52nd Electronic Component and Tech Conference,732 (2002)Google Scholar
5Song, J.Y.Yu, J.: Residual stress measurements in electroless plated Ni–P films. Thin Solid Films 415, 167 2002CrossRefGoogle Scholar
6Sohn, Y.C., Yu, J., Kang, S.K., Shih, D.Y.Lee, T.Y.: Spalling of intermetallic compounds during the reaction between lead-free solders and electroless Ni–P metallization. J. Mater. Res. 19, 2428 2004CrossRefGoogle Scholar
7Sohn, Y.C.Yu, J.: Correlation between chemical reaction and brittle fracture found in electroless Ni(P)/immersion gold-solder interconnection. J. Mater. Res. 20, 1931 2005Google Scholar
8Min, H., Chen, Z.Qi, G.: Solid state interfacial reaction of Sn–37Pb and Sn–3.5Ag solders with Ni–P under bump metallization. Acta Mater. 52, 2047 2004Google Scholar
9Wu, C.M.L.Law, C.M.T.: Microstructure evolution and shear strength of eutectic Sn–9Zn and Sn–0.7Cu lead-free BGA solder balls. Proc. HDP 04, 47 2004Google Scholar
10Mavoori, H., Chin, J., Vaynman, S., Moran, B., Keer, L.Fine, M.E.: Creep, stress relaxation, and plastic deformation in Sn–Ag and Sn–Zn eutectic solders. J. Electron. Mater. 41, 1269 1997Google Scholar
11Chonan, Y., Komiyama, T., Onuki, J., Urao, R., Kimura, T.Nagano, T.: Influence of P content in electroless plated Ni–P alloy film on interfacial structures and strength between Sn–Zn solder and plated Au/Ni–P alloy film. Mater. Trans. 43, 1887 2002CrossRefGoogle Scholar
12Lin, K.L.Shih, C.L.: Wetting interaction between Sn–Zn–Ag solders and Cu. J. Electron. Mater. 32, 95 2003CrossRefGoogle Scholar
13Yu, D.Q., Xie, H.P.Wang, L.: Investigation of interfacial microstructure and wetting property of newly developed Sn–Zn–Cu solders with Cu substrate. J. Alloys Compd. 385, 119 2004Google Scholar
14Takemoto, T., Funaki, T.Matsunawa, A.: Electrochemical investigation on the effect of silver addition on wettability of Sn–Zn system lead-free solder. Welding Res. Abroad 46, 20 2000Google Scholar
15Date, M., Shoji, T., Fujiyoshi, M., Sato, K.Tu, K.N.: Ductile-to-brittle transition in Sn–Zn solder joints measured by impact test. Scripta Mater. 51, 641 2004CrossRefGoogle Scholar
16Jee, Y.K., Ko, Y.H.Yu, J.: Effect of Zn on the intermetallics formation and reliability of Sn–3.5Ag solder on a Cu pad. J. Mater. Res. 22 (2007, in press)Google Scholar
17JESD22-B111 Board Level Drop Test Method of Components for Handheld Electronic Components (JEDEC Solid State Technology Association 2003Google Scholar
18Choi, W.K.: Interfacial phenomena and characterization of Sn-Ag-based solder alloy systems for electronic packaging. Ph.D. Thesis, Korea Advanced Institute of Science and Technology, Daejeon, Korea (2001)Google Scholar
19Cullity, B.D.: Elements of X-ray Diffraction Prentice Hall 2001Google Scholar
20Yu, J., McMahon, C.J. Jr.: The effect of composition and carbide precipitation on temper embrittlement of 2.25Cr–1Mo Steel, Part I. Effect of P and Sn. Metall. Trans. 11, 277 1980CrossRefGoogle Scholar
21Yu, J., Sohn, Y.C., Kim, J.Y., Jee, Y.K.Ko, Y.H. Impact reliabilities of lead-free solder joints with Ni(P), Cu and Ni metallizations. inProc. International Conference on Electronics Packaging, 271 (2006)Google Scholar
22Jang, J.W., Kim, P.G., Tu, K.N., Frear, D.R.Thomson, P.: Solder reaction-assisted crystallization of electroless Ni-P under bump metallization in low cost flip chip technology. J. Appl. Phys. 85, 8456 1999Google Scholar
23Chan, Y.C., Chiu, M.Y.Chuang, T.H.: Intermetallic compounds formed during the soldering reactions of eutectic Sn–9Zn with Cu and Ni substrates. Z. Metallkde. 93, 95 2002Google Scholar
24Knott, J.F.: Fundamentals of Fracture Mechanics Butterworths London, UK 1973 147Google Scholar