Hostname: page-component-78c5997874-t5tsf Total loading time: 0 Render date: 2024-11-14T23:51:45.783Z Has data issue: false hasContentIssue false
  • English
  • Français

Effects of under bump metallization and nickel alloying element on the undercooling behavior of Sn-based, Pb-free solders

Published online by Cambridge University Press:  31 January 2011

Moon Gi Cho ,
Sung K. Kang ,
Sun-Kyoung Seo ,
Da-Yuan Shih  and
Hyuck Mo Lee
Moon Gi Cho
Affiliation:
Department of Materials Science and Engineering, KAIST Yuseong-gu, Daejeon, Republic of Korea 305-701
Sung K. Kang
Affiliation:
IBM T.J. Watson Research Center, Yorktown Heights, New York 10598
Sun-Kyoung Seo
Affiliation:
Department of Materials Science and Engineering, KAIST Yuseong-gu, Daejeon, Republic of Korea 305-701
Da-Yuan Shih
Affiliation:
IBM T.J. Watson Research Center, Yorktown Heights, New York 10598
Hyuck Mo Lee*
Affiliation:
Department of Materials Science and Engineering, KAIST Yuseong-gu, Daejeon, Republic of Korea 305-701
*
a) Address all correspondence to this author. e-mail: hmlee@kaist.ac.kr
Get access

Abstract

A significant reduction of the undercooling of Sn-based solder alloys was previously reported when they were reacted with various under bump metallurgies (UBMs). In the present study, new experiments have been designed and carried out to understand the undercooling behavior of various Cu- and Ni-doped solders on Ni UBM. Two competing mechanisms were further investigated that include the formation of intermetallic compounds (IMCs) at solder/UBM interface and the change of solder composition because of the dissolution of Ni UBM into solder. Two types of IMCs, including both Ni3Sn4 and Cu6Sn5 that were formed at the interface, were correlated with the undercooling of Sn–0.2Cu and Sn–3.8Ag–0.2Cu solders. In addition, the compositional changes of various Sn-based solders after reactions with Ni UBM were analyzed. On the basis of the experimental results, it was found that the significant reduction in undercooling is primarily caused by dissolved Ni atoms from Ni UBM and the concurrent formation of Ni3Sn4 IMC in the solder matrix. Finally, the beneficial effect of Ni dissolution is thermodynamically favorable as confirmed by the thermodynamic calculations and differential scanning calorimetry measurements with various Ni-doped solder alloys.

Keywords

Differential thermal analysis (DTA)MicrostructureNi
Type
Articles
Information
Journal of Materials Research , Volume 24 , Issue 2 , February 2009 , pp. 534 - 543
Copyright
Copyright © Materials Research Society 2009

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., Lauro, P., Shih, D.-Y., Henderson, D.W., Puttlitz, K.J.: The microstructure, solidification, mechanical properties, and thermal fatigue behavior of lead (Pb)-free solders and solder joints used in microelectronic applications. IBM J. Res. Dev. 49, (4/5)607 (2005)CrossRefGoogle Scholar
2.Vonnegut, B.: Variation with temperature of the nucleation rate of supercooled liquid tin and water drops. J. Colloid Sci. 3, 563 (1948)Google Scholar
3.Pound, G.M., Mer, V.K.L.A.: Kinetics of crystalline nucleus formation in supercooled liquid tin. J. Am. Chem. Soc. 74, 2323 (1952)Google Scholar
4.Kang, S.K., Choi, W.K., Shih, D-Y., Henderson, D.W., Gosselin, T., Sarkhel, A., Goldsmith, C., Puttlitz, K.J.: Formation of Ag3Sn plates in Sn–Ag–Cu alloys and optimization of their alloy composition, in Proc. 53rd Electronic Components and Technology ConferenceIEEE, Piscataway, NJ 2003)6470Google Scholar
5.Lehman, L.P., Kinyanjui, R.K., Zavalij, L., Zribi, A., Cotts, E.J.: Growth and selection of intermetallic species in Sn–Ag–Cu, No-Pb, solder systems based on pad metallurgies and thermal histories, in Proc. 53rd Electronic Components and Technology ConferenceIEEE, Piscataway, NJ 2003)12151221Google Scholar
6.Kang, S.K., Shih, D-Y., Leonard, D., Henderson, D.W., Gosselin, T., Cho, S-I., Yu, J., Choi, W.K.: Controlling Ag3Sn plate formation in near-ternary-eutectic Sn–Ag–Cu solder by minor Zn alloying. JOM 56, (6)34 (2004)CrossRefGoogle Scholar
7.Xiao, Q., Nguyen, L., Armstrong, W.D.: The anomalous microstructural, tensile, and aging response of thin-cast Sn3.9Ag0.6Cu lead-free solder. J. Electron. Mater. 34, (5)617 (2005)Google Scholar
8.Cho, M.G., Kang, S.K., Lee, H.M.: Undercooling and microhardness of Pb-free solders on various under bump metallurgies. J. Mater. Res. 23, (4)1147 (2008)Google Scholar
9.Kang, S.K., Cho, M.G., Lauro, P., Shih, D-Y.: Critical factors affecting the undercooling of Pb-free, flip-chip solder bumps and in-situ observation of solidification process, in Proc. 57th Electronic Components and Technology ConferenceIEEE, Piscataway, NJ 2007)15971603CrossRefGoogle Scholar
10.Kang, S.K., Cho, M.G., Shih, D-Y., Seo, S-K., Lee, H.M.: Controlling the interfacial reactions in Pb-free interconnections by adding minor alloying elements to Sn-rich solders, in Proc. 58th Electronic Components and Technology ConferenceIEEE, Piscataway, NJ 2008)478484Google Scholar
11.Ho, C.E., Yang, S.C., Kao, C.R.: Interfacial reaction issues for lead-free electronic solders. J. Mater. Sci.-Mater. Electron. 18, 155 (2007)CrossRefGoogle Scholar
12.Chen, S-W., Wang, C-H.: Interfacial reactions of Sn–Cu/Ni couples at 250 °C. J. Mater. Res. 21, (9)2270 (2006)Google Scholar
13.Sundman, B., Jansson, B., Andersson, J.O.: The Thermo-Calc databank system. Calphad 9, 153 (1985)CrossRefGoogle Scholar
14.Ghosh, G.: Thermodynamic modeling of the nickel-lead-tin system. Metall. Mater. Trans. A 30, 1481 (1999)CrossRefGoogle Scholar
15.Kim, J.H., Jeong, S.W., Kim, H.D., Lee, H.M.: Morphological transition of interfacial Ni3Sn4 grains at Sn–3.5Ag/Ni joint. J. Electron. Mater. 32, (11)1228 (2003)CrossRefGoogle Scholar
16.Choi, W.K., Lee, H.M.: Prediction of primary intermetallic compound formation during interfacial reaction between Sn-based solder and Ni substrate. Scr. Mater. 46, (11)777 (2002)CrossRefGoogle Scholar
17.Zeng, K., Vuorinen, V., Kivilahti, J.K.: Interfacial reactions between lead-free SnAgCu solder and Ni(P) surface finish on printed circuit boards. IEEE Trans. Electron. Packag. Manuf. 25, 162 (2002)CrossRefGoogle Scholar
18.Laurila, T., Vuorinen, V., Kivilahti, J.K.: Interfacial reactions between lead-free solders and common base materials. Mater. Sci. Eng., R 49, 1 (2005)CrossRefGoogle Scholar
19.Zeng, K., Tu, K.N.: Six cases of reliability study of Pb-free solder joints in electronic packaging technology. Mater. Sci. Eng., R 38, 55 (2002)CrossRefGoogle Scholar
20.Binary Alloy Phase Diagrams edited by T.B. Massalski (ASM International Metal Park, OH 1990)1481Google Scholar
21.Moon, K-W., Boettinger, W.J., Kattner, U.R., Biancaniello, F.S., Handwerker, C.A.: Experimental and thermodynamic assessment of Sn–Ag–Cu solder alloys. J. Electron. Mater. 29, 1122 (2000)Google Scholar
22.Nash, P., Nash, A.: The Ni–Sn system. Bull. Alloy Phase Diag. 6, 350 (1985)CrossRefGoogle Scholar