Morphology of instability of the wetting tips of eutectic SnBi, eutectic SnPb, and pure Sn on Cu
- 3 March 1995
- journal article
- Published by Springer Nature in Journal of Materials Research
- Vol. 10 (3) , 497-504
- https://doi.org/10.1557/jmr.1995.0497
Abstract
The Pb-based solder used in microelectronics industry is becoming an environmental issue. To understand the wetting behavior of solders with and without Pb, we have studied the surface morphology and wetting reaction of eutectic SnBi, eutectic SnPb, and pure Sn on Cu through the measurements of wetting angle change and wetting tip stability by SEM and EDX. The wetting angle remains constant after the initial spread, but the eutectic SnPb/Cu continues to react and forms a reaction band in front of the solder edge as well as intermetallic compounds at the interface. For eutectic SnBi/Cu, there is no reaction at the wetting tip, and the wetting angle does not change much; however, the interfacial reaction between eutectic SnBi and Cu forms intermetallic compounds at the solder joint; the wetting tip is not in a static equilibrium. A rough surface and edge was observed on the eutectic SnBi/Cu joint, but the eutectic SnPb/Cu has a smoother surface and edge.Keywords
This publication has 11 references indexed in Scilit:
- Characterization of eutectic Sn-Bi solder jointsJournal of Electronic Materials, 1992
- Microelectronics Packaging HandbookJournal of Electronic Packaging, 1989
- Principles of Electronic PackagingJournal of Electronic Packaging, 1989
- The effect of Cu6Sn5 whisker precipitates in bulk 60sn-40pb solderJournal of Electronic Materials, 1987
- The formation of Cu3Sn intermetallic on the reaction of cu with 95Pb-5Sn solderJournal of Electronic Materials, 1986
- Kinetics of interfacial reaction in bimetallic CuSn thin filmsActa Metallurgica, 1982
- Wetting under chemical equilibrium and nonequilibrium conditionsThe Journal of Physical Chemistry, 1974
- Interdiffusion and reaction in bimetallic Cu-Sn thin filmsActa Metallurgica, 1973
- Interstitial Diffusion of Copper in TinJournal of Applied Physics, 1967
- III. An essay on the cohesion of fluidsPhilosophical Transactions of the Royal Society of London, 1805