Abstract
The European requirement for lead-free electronics has resulted in higher soldering temperature and some material and process changes. Traditional tin-lead solder melts at 183°C, where as the most common lead-free alternatives have a much higher melting temperature—tin-copper (227°C), tin-silver (221°C) and tin-silver-copper (217°C). These have challenged the ingenuity of the materials and process engineers. This chapter will explore some of the issues that have come up in this transition, and which these engineers have understood and addressed. As we enter the lead-free era, we see changes as printed wiring board (PWB) substrates which were designed for lower soldering temperatures are being replaced by newer materials. Factors such as glass transition temperature (T g), decomposition temperature (T d) and coefficient of thermal expansion must be considered. Many electronic components are made for lower peak temperatures than those required by the new solders. Solder flux chemistries are changing to meet the needs of the new metal systems, and cleaning of flux residues is becoming more of a challenge. Finally, there is a potential reliability problem—an increased potential for the growth of conductive anodic filament (CAF), an electrochemical failure mechanism that occurs in the use environment.
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References
B. McGrath, The effects of Lead-free on PCB Fabrication, (Printed Circuit Design and Manufacture, February, 2005), pp. 44–47
E. Kelley, in Proceedings of Nordic Conference on Printed Circuit Board Quality, Lillestróm, Norway, 21–22, September 2004
Louis T. Mazione, Plastic Packaging of Microelectronic Devices. (Van Nostrand Reinhold, New York, 1990), p. 63
C.J. Smithells, Metals Reference Book, vol. 3, 4th edn. (Butterworths, London, 1967), p. 687
Electronics Materials Handbook, vol. 1, Packaging, (ASM International, Materials Park, OH, 1989), p. 639
C.A. Handwerker, F.W. Gayle, E.E. de Kluizenar, K. Sugauma, in Handbook of Lead-Free Solder Technology for Microelectronic Assemblies, ed. by K.J. Puttlitz, K.A. Stalter (Marcel Dekker, New York, 2004), p. 698
http://www.metallurgy.nist.gov/solder/clech/Sn-Ag_Other.htm#Coefficients
Electronics Materials Handbook, vol. 1, Packaging, (ASM International, Materials Park, OH, 1989), p. 468
V.T. Brzozowski, R.N. Horton, in Electronic Packaging and Interconnect Handbook, ed. by Charles A. Harper (McGraw Hill, New York, 1991), p. 8.44
W. Engelmaier (2005), IPC Technet Archives. http://www.listserv.ipc.org/archives/technet.html. Cited 13 Dec 2005
J. Fellman, in Proceedings of International Conference on Lead-free Soldering, Toronto, Ontario, 16–18, May 2006
G.L. Fisher, W. Sonnenberg, R. Bernards, Printed Circuit Fabri. 12(4) (1989)
Terms and Definitions for Interconnecting and Packaging Electronic Circuits, (ANSI/IPC-T-50) published by the IPC, 3000 Lakeside Drive, 309 S, Bannockburn, IL 60015
Peter Biocca, in Proceedings of SMTA International, Chicago, Illinois, 30 September 2001
Requirements for Soldering Fluxes, published by IPC, 3000 Lakeside Drive, 309 S, Bannockburn, IL 60015
Moisture/Reflow Sensitivity Classification for Nonhermetic Solid State Surface Mount Devices, IPC/JEDEC J-STD-020C, published jointly by IPC, 3000 Lakeside Drive, 309 S, Bannockburn, IL 60015
L.J. Turbini, W.R. Bent, W.J. Ready, J. Surf. M. Technol. 13, 4 (2000)
P.J. Boddy, R.H. Delaney, J.N. Lahti, E.F. Landry, in 14th Annual Proceedings of Reliability Physics, 108 (1976)
D.J. Lando, J.P. Mitchell, T.L. Welsher, in 17th Annual Proceedings of Reliability Physics, 51 (1979)
J.N. Lahti, R.H. Delaney, J.N. Hines, in 17th Annual Proceedings of Reliability Physics, 39 (1979)
W.J. Ready, L.J. Turbini, L.J., S.R. Stock, B.A. Smith, in 34th Annual Proceedings of Reliability Physics, 267 (1996)
J.A. Jachim, G.F. Freeman, L.J. Turbini, IEEE T. Compon. Pack. B, 20(4), 443 (1997)
J. Brous, in Proceedings of NEPCON West 1992, 386 (1992)
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Turbini, L.J. (2006). Processing and material issues related to lead-free soldering. In: Lead-Free Electronic Solders. Springer, Boston, MA. https://doi.org/10.1007/978-0-387-48433-4_9
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DOI: https://doi.org/10.1007/978-0-387-48433-4_9
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