Fachbereich 11 - Physik
Institut für Materialphysik
Nanoanalysis of Interreactions

Growth morphology of Cu/SnPb solder reaction

Soldering is one of the oldest joining techniques for metals. Down-scaling of packaging in microelectronics requires a more detailed understanding of the reaction between the solid metal and the liquid solder. The mechanical stability of the joints depends on the formation of an intermetallic compound inside the reaction zone. In our experiments we studied the reaction of Cu with liquid Sn as well as with liquid SnPb. In both cases no planar reaction product is formed, but a scallop like structure. This is distinguished by liquid channels allowing the fast transport across the intermetallic, so that rather high reaction rates result that hinder the further down scaling of solder joints.

Drittmittelgeber:

Alexander von Humboldt-Stiftung

Beteiligte Wissenschaftler:

J. Görlich (Univ. Göttingen), K.N. Tu (Univ. California Los Angeles), G. Schmitz (Projektleiter)