Fast soldering reactions on Au foils

P. G. Kim*, King-Ning Tu

*Corresponding author for this work

Research output: Contribution to journalConference articlepeer-review

7 Scopus citations


We have studied the wetting behaviors and interfacial reactions of Pb-containing (63Sn-37Pb, 95Pb-5Sn) and Pb-free solders (pure Sn, 96Sn-4Ag, 57Bi-43Sn, 77.2Sn-20In-2.8Ag) on Au foils in order to understand the role of Pb in Pb-based solders. Surface morphology, wetting angle, and interfacial reaction of the solders were studied by Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Analysis (EDX). Pb-containing and Pb-free solders (pure Sn, 96Sn-4Ag, 77.2Sn-20In-2.8Ag) showed rough surfaces due to the precipitation of intermetallic compounds on the surface of the solder caps. The eutectic SnBi (57Bi-43Sn) solder, however, showed a smoother surface. The wetting angle of the eutectic SnPb (63Sn-37Pb), pure Sn, 96Sn-4Ag, and 77.2Sn-20In-2.8Ag solders decreased significantly with reflow time, while the eutectic SnBi and 95Pb-5Sn solders showed a much smaller decrease. A large amount of intermetallic compounds was formed throughout the entire region of the solder cap for the eutectic SnPb, 96Sn-4Ag, 95Pb-5Sn, and 77.2Sn-20In-2.8Ag, mainly due to the high solubility of Au in these solders. Slow intermetallic compound growth was observed for the eutectic SnBi solder.

Original languageEnglish
Pages (from-to)131-136
Number of pages6
JournalMaterials Research Society Symposium - Proceedings
StatePublished - 1 Dec 1997
EventProceedings of the 1996 MRS Fall Symposium - Boston, MA, USA
Duration: 3 Dec 19965 Dec 1996

Fingerprint Dive into the research topics of 'Fast soldering reactions on Au foils'. Together they form a unique fingerprint.

Cite this