Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-26T22:51:49.651Z Has data issue: false hasContentIssue false

Intermetallic compound spalling characteristics of Sn-3.5Ag solder over ternary electroless Ni under-bump metallurgy

Published online by Cambridge University Press:  17 November 2011

Dong Min Jang
Affiliation:
Samsung Electronics, Hwasung-City, Gyeongii-Do 445-701, Korea
Jin Yu*
Affiliation:
Electronic Packaging Laboratory, Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology, Yuseong-gu, Daejeon 305-701, Korea
*
a)Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

Ternary electroless nickel, NiXP, films were produced by adding salts of Mo, Re, Tl, Cu, W, Co, Fe, Zn, and Mn to conventional electroless Ni baths and subsequently reacted with Sn-3.5Ag solder. From the full width at the half maximum (FWHM) data, as-plated NiXP films can be categorized into two groups: one is close to the FWHM value of nanocrystalline Ni5P film and the other is close to amorphous Ni9P film. Alloying elements in the electrolessly plated under-bump metallurgy that effectively suppressed intermetallic compound (IMC) spalling were Mn, Zn, Re, Fe, and W, whereas Tl exacerbated spalling. The roles of Cu, Mo, and Co were less clear due to a lack of data. Based on scanning electron microscopy observations, a spalling map was presented, which showed elemental demarcation lines of IMC spalling in the X-P coordinates.

Type
Articles
Copyright
Copyright © Materials Research Society 2011

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

1.Kang, S.K., Rai, R.S., and Purushothaman, S.: Interfacial reactions during soldering with lead-tin eutectic and lead (Pb)-free, tin-rich solders. J. Electron. Mater. 25, 1113 (1996).CrossRefGoogle Scholar
2.Jee, Y.K., Yu, J., and Ko, Y.H.: Effects of Zn addition on the drop reliability of Sn–3.5Ag–xZn/Ni(P) solder joints. J. Mater. Res. 22, 2776 (2007).CrossRefGoogle Scholar
3.Kim, J.Y., Sohn, Y.C., and Yu, J.: Effect of Cu content on the mechanical reliability of Ni/Sn-3.5Ag system. J. Mater. Res. 22, 770 (2007).CrossRefGoogle Scholar
4.Min, H., Chen, Z., and Qi, G.: Solid state interfacial reaction of Sn–37Pb and Sn–3.5Ag solders with Ni–P under bump metallization. Acta Mater. 52, 2047 (2004).Google Scholar
5.Jee, Y.K., Ko, Y.H., and Yu, J.: Effect of Zn on the intermetallics formation and reliability of Sn-3.5Ag solder on a Cu pad. J. Mater. Res. 22, 1879 (2007).CrossRefGoogle Scholar
6.Yoon, J.W., Kim, S.W., and Jung, S.B.: IMC morphology, interfacial reaction and joint reliability of Pb-free Sn-Ag-Cu solder on electrolytic Ni BGA substrate. J. Alloys Compd. 392, 247 (2005).CrossRefGoogle Scholar
7.Sohn, Y.C., Yu, J., Kang, S.K., Shih, D.Y., and Lee, T.Y.: Spalling of intermetallic compounds during the reaction between lead-free solders and electroless Ni–P metallization. J. Mater. Res. 19, 2428 (2004).CrossRefGoogle Scholar
8.Sohn, Y.C. and Yu, J.: Correlation between chemical reaction and brittle fracture found in electroless Ni(P)/immersion gold-solder interconnection. J. Mater. Res. 20, 1931 (2005).CrossRefGoogle Scholar
9.Kim, H.K., Tu, K.N., and Totta, P.A.: Ripening-assisted asymmetric spalling of Cu-Sn compound sheroids in solder joints on Si wafers. Appl. Phys. Lett. 68, 2204 (1996).CrossRefGoogle Scholar
10.Liu, A.A., Kim, H.K., Tu, K.N., and Totta, P.A.: Spalling of Cu6Sn5 spheroids in the soldering reaction of eutectic SnPb on Cr/Cu/Au thin films. J. Appl. Phys. 80, 2774 (1996).CrossRefGoogle Scholar
11.Li, J.F., Mannan, S.H., Clode, M.P., Whalley, D.C., and Hutt, D.A.: Interfacial reactions between molten Sn–Bi–X solders and Cu substrates for liquid solder interconnects. Acta Mater. 54, 2907 (2006).CrossRefGoogle Scholar
12.Kang, S.K., Shih, D.Y., and Sohn, Y.C.: Prevention and control of intermetallic alloy inclusions that form during reflow of Pb free, Sn rich, solders in contacts in microelectronic packaging in integrated circuit contact structures where electroless Ni(P) metallization is present. US Patent 2006/0024943 A1 (February 2, 2006).Google Scholar
13.Pearlstein, F. and Weightman, R.F.: Electroless deposition of nickel alloys. Electrochem. Technol. 6, 427 (1968).Google Scholar
14.Mallory, G.O. and Horhn, T.R.: Electroless deposition of ternary alloys. Plat. Surf. Finish. 66, 40 (1979).Google Scholar
15.Hsu, J. and Lin, K.: Enhancement in the deposition behavior and deposit properties of electroless Ni-Cu-P. J. Electrochem. Soc. 150, C653 (2003).CrossRefGoogle Scholar
16.Schmeckenbecher, A.F.: Chemical nickel-iron films. J. Electrochem. Soc. 113, 778 (1966).CrossRefGoogle Scholar
17.Sankara, T.S.N., Selvakumar, S., and Stephen, A.: Electroless NiCoP ternary alloy deposits: Preparation and characteristics. Surf. Coat. Technol. 172, 299 (2003).Google Scholar
18.Bouanani, M., Cherkaoui, F., Fratesi, R., Roventi, G., and Barucca, G.: Microstructural characterization and corrosion resistance of Ni-Zn-P alloys electrolessly deposited from a sulphate bath. J. Appl. Electrochem. 29, 637 (1999).CrossRefGoogle Scholar
19.Osaka, T., Kasai, N., Koiwa, I., and Goto, F.: A study on electroless plating of cobalt alloy films for perpendicular recording. J. Electrochem. Soc. 130, 790 (1983).CrossRefGoogle Scholar
20.Chen, K., Liu, C., Whalley, D.C., and Hutt, D.A.: Electroless Ni-W-P alloys as barrier coatings for liquid solder interconnects, in Proceedings of the 1st Electronics Systemintegration Technology Conference, Vol. 1, September 5-7, 2006, pp. 421427.Google Scholar
21.Jang, D.M. and Yu, J.: Tungsten alloying of the Ni(P) films and the reliability of Sn-3.5Ag/NiWP solder joints. J. Mater. Res. 26, 889 (2011).CrossRefGoogle Scholar
22.Tai, F.C., Wang, K.J., and Duh, J.G.: Application of electroless Ni–Zn–P film for under-bump metallization on solder joint. Scr. Mater. 61, 748 (2009).CrossRefGoogle Scholar
23.Ratchev, P., Labie, R., and Beyne, E.: Nanohardness study of CoSn2 intermetallic layers formed between Co UBM and Sn flip-chip, in Proceedings of 6th Electronic Packaging Technology Conference, December 8-10, 2004, pp. 339342.Google Scholar
24.He, M., Chen, Z., and Qi, G.: Solid state interfacial reaction of Sn–37Pb and Sn–3.5Ag solders with Ni–P under bump metallization. Acta Mater. 52, 2047 (2004).CrossRefGoogle Scholar
25.Yang, Y., Lim, Y.J., Kumar, A., Lee, T.K., and Chen, Z.: Interface reactions and shear strength of lead-free Sn-3.5Ag solder with Ni-W-P metallization, in Proceedings of the 9th Electronic Packaging Technology Conference, December 10-12, 2007, pp. 527532.Google Scholar