Evaluation of Alloying Additions on the Microstructure and IMC Formation of Sn-Ag-Cu Solder on Cu and Ni (P) Substrates
Authors: S.O. Shazlin, M.S. Nurulakmal
Abstract:
Studies have shown that the SnAgCu solder family has been widely used as a replacement for conventional Sn-Pb solders. An attractive approach is by introducing alloying additives (rare earth elements (RE), Zn, Co, Fe, Ni, Sb) into the SnAgCu solder, which helps in refining the microstructure also improving the mechanical and wetting properties of the solder. The present work focuses on the effect of additions of 0.5% Ce and Fe into Sn-3.0Ag-0.5Cu solder, in attempt to reduce the intermetallic compound (IMC) growth and reflow properties of the solder on Cu and Ni (P) surface finish, as well as effects thermal aging on the formation of intermetallic compound (IMC) on different surface finish. Excessive intermetallic compound growth may effect the interface and solder joint due to the brittle nature of the intermetallic compounds. Thus, by introducing alloying elements, IMC layer thickness can be decrease, resulting in better joint and solder reliability.
Keywords: Alloying Elements, Cu and Ni (P) Substrate, Intermetallic Compound (IMC), Reflow, Thermal Aging.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1077896
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1607References:
[1] L. Gao, S. Xue, L. Zhang, Z. Sheng, F. Ji, W. Dai, S. Yu, G. Zeng, "Effect of alloying elements on properties and microstructures of SnAgCu solders," Microelectronic Engineering, vol. 87, pp. 2025-2034, 2010.
[2] L. Zhang, S. Xue, L.Gao, Y.Chen, S.Yu, Z.Sheng, G.Zeng "Effects of trace amount addition of rare earth on properties and microstructure of Sn—Ag—Cu alloys," J Mater Sci: Mater Electron, vol. 20, pp. 1193-1199, 2009.
[3] G.Y. Li, B.L. Chen, X.Q. Shi, S.C.K. Wong, Z.F. Wang, "Effects of Sb addition ontensile strength of Sn-3.5Ag-0.7Cu solder alloy joint," Thin Solid Films, vol. 504, pp.421-425, 2006.
[4] D.Q. Yu, J. Zhao, L. Wang, "Improvement on the microstructure stability, mechanical and wetting properties of Sn-Ag-Cu lead-free solder with the addition of rare earth elements," Journal of Alloys and Compounds, vol. 376, pp. 170-175, 2004.
[5] W. Yang, L.E. Feltron, R.W. Messler Jr., "The effect of soldering process variables on the microstructure and mechanical properties of eutectic Sn-Ag/Cu solder joints", J. Electron. Mater., vol. 24, no. 10, pp.1465— 1472, 1995.
[6] S. Choi, T.R. Bieler, J.P. Lucas, K.N. Subramanian, ./. Electron. Mater., vol. 28, pp. 1209-1215, 1999.
[7] S.W. Chen, Y.W. Yen, "Interfacial reactions in Ag-Sn/Cu couples, " J. Electron Mater, vol. 28, pp. 1203-1208, 1999.
[8] W.K. Choi and H.M. Lee, "Effect of Soldering and Aging Time on Interfacial Microstructure and Growth of Intermetallics Between Sn-Ag Solder and Cu substrates," J. Electron. Mater., vol. 29, no. 10, pp. 1207¬1213, 2000.
[9] L. Gao, S. Xue, L. Zhang, Z. Sheng, F. Ji, W. Dai, S. Yu, G. Zeng, "Effect of alloying elements on the properties and microstructure of SnAgCu solders," Microelectronic Engineering, vol. 87, pp. 2025-2034, 2010.
[10] L. Zhang, S. Xue, L.Gao, Y.Chen, S.Yu, Z.Sheng, G.Zeng, "Effects of trace amount addition of rare earth on properties and microstructure of Sn-Ag-Cu alloys," J Mater Sci: Mater Electron, vol. 20, pp. 1193-1199, 2009.
[11] L. Liang, Q. Wang, Z. Zhao, "Effect of cerium addition on board level reliability of Sn-Ag-Cu solder joint," IEEE Xplore, 2007.
[12] Y.W. Wang, Y.W. Lin, C.T. Tu, C.R. Kao, "Effect of minor Fe, Co, and Ni additions on the reaction between SnAgCu solder and Cu," Journal of Alloys and Compounds, vol. 478, pp. 121-127, 2009.
[13] A. Kumar, Z. Chen, S.G. Mhaisalkar, C.C. Wong, P.S. Teo, V. Kripesh, "Effect of Ni-P thickness on solid-state interfacial reactions between Sn-3.5Ag solder and electroless Ni-P metallization on Cu substrate," Thin Solid Films, vol. 504, pp. 410 — 415, 2006.