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Intermetallic formation induced substrate dissolution in electroless Ni(P)-solder interconnections

Published online by Cambridge University Press:  31 January 2011

Jenn-Ming Song*
Affiliation:
Department of Materials Science and Engineering and Nanotechnology Research Center, National Dong Hwa University, 974 Hualien, Taiwan, Republic of China
Yao-Ren Liu
Affiliation:
Department of Materials Science and Engineering and Nanotechnology Research Center, National Dong Hwa University, 974 Hualien, Taiwan, Republic of China
Chien-Wei Su
Affiliation:
Department of Materials Science and Engineering and Nanotechnology Research Center, National Dong Hwa University, 974 Hualien, Taiwan, Republic of China
Yi-Shao Lai
Affiliation:
Central Labs, Advanced Semiconductor Engineering, Inc., Nantze Export Processing Zone, 811 Nantze, Kaohsiung, Taiwan, Republic of China
Ying-Ta Chiu
Affiliation:
Central Labs, Advanced Semiconductor Engineering, Inc., Nantze Export Processing Zone, 811 Nantze, Kaohsiung, Taiwan, Republic of China
*
a)Address all correspondence to this author. e-mail: samsong@mail.ndhu.edu.tw
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Abstract

The effect of minor transition metal (TM) additives of Ni, Co, or Zn on the interfacial reactions of the solder joints between Sn–Ag–Cu (SAC) solder and the Cu/Ni(P)/Au substrate was investigated, especially subsequent to multi-reflowing. (Cu,Ni)6Sn5 formed at the interface of all the joints except that of SAC–Ni, of which the interfacial compound was (Ni,Cu)6Sn5. The interfacial compounds of the SAC–Co and SAC–Zn contained a small amount of alloying elements of less than 3 at.%. Two P-rich layers, Ni3P and Ni–Sn–P emerged at the interface of the SAC joints. Nanoindentation analysis indicates that the hardness and Young’s modulus of these two phases were slightly higher than those of the Ni(P) substrate, which were in turn much greater than those of the Cu–Ni–Sn compounds. Worthy of notice is that with TM additions, the Ni–Sn–P phase between Ni3P and interfacial compounds was absent even after 10 reflows. For the SAC–Co joints, the growth of Ni-containing intermetallic compounds within the solder gave rise to the excess Ni dissolution, which caused a discrete Ni3P layer and over-consumed Ni(P) substrate underneath the grooves in-between (Cu, Ni)6Sn5 scallop grains at the interface. This phenomenon is presented for the first time, and the mechanism is proposed in this study.

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Articles
Copyright
Copyright © Materials Research Society 2008

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References

REFERENCES

1Anderson, I.E., Cook, B.A., Harringa, J.Terpstra, R.L.: Sn–Ag–Cu solders and solder joints: Alloy development, microstructure, and properties. JOM 54(6), 26 2002CrossRefGoogle Scholar
2Wable, G.S., Chada, S., Neal, B.Fournelle, R.A.: Solidification shrinkage defects in electronic solders. JOM 57(6), 28 2005Google Scholar
3Henderson, D.W., Gosselin, T., Sarkhel, A., Kang, S.K., Choi, W.K., Shih, D.Y., Goldsmith, C.Puttlitz, K.J.: Ag3Sn plate formation in the solidification of near ternary eutectic Sn–Ag–Cu alloys. J. Mater. Res. 17, 2775 2002Google Scholar
4Frear, D.R., Jang, J.W., Lin, J.K.Zang, C.: Pb-free solders for flip-chip interconnects. JOM 53(6), 28 2001CrossRefGoogle Scholar
5Chuang, C.M.Lin, K.L.: Effect of microelements addition on the interfacial reaction between Sn–Ag–Cu solders and the Cu substrate. J. Electron. Mater. 32, 1426 2003CrossRefGoogle Scholar
6Gao, F., Takemoto, T., Nishikawa, H.Komatsu, A.: Microstructure and mechanical properties evolution of intermetallics between Cu and Sn–3.5Ag solder doped by Ni–Co additives. J. Electron. Mater. 35, 905 2006CrossRefGoogle Scholar
7Kim, K.S., Huh, S.H.Suganuma, K.: Effects of fourth alloying additive on microstructures and tensile properties of Sn–Ag–Cu alloy and joints with Cu. Microelectron. Reliab. 43, 259 2003Google Scholar
8Kang, S.K., Shih, D.Y., Leonard, D., Henderson, D.W., Gosselin, T., Cho, S., 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 2004CrossRefGoogle Scholar
9Kang, S.K., Leonard, D., Shih, D.Y., Gignac, L., Henderson, D.W., Cho, S.Yu, J.: Interfacial reactions of Sn–Ag–Cu solders modified by minor Zn alloying addition. J. Electron. Mater. 35, 479 2006CrossRefGoogle Scholar
10Lee, D.J., Baek, D.H., Lee, K.K., Lee, K.M.Seo, Y.J.: The mechanical properties of a joint of Sn–3.5Ag–1Zn solder and Cu substrate with aging treatment. Z. Metallkd. 96, 148 2005CrossRefGoogle Scholar
11Anderson, I.E., Foley, J.C., Cook, B.A., Harringa, J., Terpstra, R.L.Unal, O.: Alloying effects in near-eutectic Sn–Ag–Cu solder alloys for improved microstructural stability. J. Electron. Mater. 30, 1050 2001Google Scholar
12Anderson, I.E.Harringa, J.: Suppression of void coalescence in thermal aging of tin-silver-copper solder joints. J. Electron. Mater. 31, 94 2006Google Scholar
13Kim, S.W., Yoon, J.W.Jung, S.B.: Interfacial reactions and shear strengths between Sn–Ag-based Pb-free solder balls and Au/EN/Cu metallization. J. Elecron. Mater. 33, 1182 2004Google Scholar
14Hwang, C.W., Suganuma, K., Kiso, M.Hashimoto, S.: Influence of Cu addition to interface microstructure between Sn–Ag solder and Au/Ni–6P plating. J. Elecron. Mater. 33, 1200 2004CrossRefGoogle Scholar
15Sohn, 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
16Sohn, 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 2005CrossRefGoogle Scholar
17Vuorinen, V., Laurila, T., Yu, H.Kivilahti, L.K.: Phase formation between lead-free Sn–Ag–Cu solder and Ni(P)/Au finishes. J. Appl. Phys. 99, 023530 2006Google Scholar
18Lin, Y.C.Duh, J.G.: Phase transformation of the phosphrous-rich layer in SnAgCu/Ni-P solder joints. Scr. Mater. 54, 1661 2006CrossRefGoogle Scholar
19Lin, Y.C., Shih, T.Y., Tien, S.K.Duh, J.G.: Suppressing Ni–Sn–P growth in SnAgCu/Ni–P solder joints. Scr. Mater. 56, 49 2007Google Scholar
20Yang, S.C., Ho, C.E., Chang, C.W.Kao, C.R.: Massive spalling of intermetallic in solder-substrate reactions due to limited supply of the active element. J. Appl. Phys. 101, 084911 2007CrossRefGoogle Scholar
21Ho, C.E., Yang, S.C.Kao, C.R.: Interfacial reaction issues for lead-free electronic solders. J. Mater. Sci.-Mater. Electron. 18, 155 2007CrossRefGoogle Scholar
22Oliver, W.C.Pharr, G.M.: An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments. J. Mater. Res. 7, 1564 1992Google Scholar
23Jang, G.Y., Lee, J.W.Duh, J.G.: The nanoindentation characteristics of Cu6Sn5, Cu3Sn, and Ni3Sn4 intermetallic compounds in the solder bump. J. Electron. Mater. 33, 1103 2004Google Scholar
24Chemistry: Molecules, Matter, and Change, 4th ed. edited by L. Jones and P. Atkins W.H. Freeman and Company New York 2000Google Scholar
25Song, J.M., Huang, C.F.Chuang, H.Y.: Microstructural characteristics and vibration fracture properties of Sn–Ag–Cu–TM (TM = Co, Ni and Zn) alloys. J. Electron. Mater. 35, 2154 2006Google Scholar
26Powder Diffraction Files 48-1813 published by International Center for Diffraction Data (ICDD) Newton Square, PAGoogle Scholar
27Siewert, T., Smith, D.R., Madeni, J.C.Liu, S.: Zeroing in on a lead-free solder database. Welding J. 84, 30 2005Google Scholar
28Zeng, K., Vuorinen, V.Kivilahti, J.: Interfacial reactions between lead-free SnAgCu solder and Ni(P) surface finish on printed circuit boards. IEEE Trans. Electron. Packaging Manuf. 25, 162 2002CrossRefGoogle Scholar
29Dybkov, V.I.: Interaction of iron-nickel alloys with liquid aluminum: Part 1. Dissolution kinetics. J. Mater. Sci. 28, 6371 1993CrossRefGoogle Scholar
30Kim, H.K.Tu, K.N.: Kinetic analysis of the soldering reaction between eutectic Sn–Pb alloy and Cu accompanied by ripening. Phys. Rev. B 53, 16027 1996CrossRefGoogle Scholar
31Ma, D., Wang, W.D.Lahiri, S.K.: Scallop formation and dissolution of Cu–Sn intermetallic compounds during solder reflow. J. Appl. Phys. 91, 3312 2002Google Scholar