2001 Volume 42 Issue 7 Pages 1423-1427
The fluxless wetting properties were evaluated for TSM (Top Surface Metallurgy)-coated glass substrate by wetting balance method. The wettability of TSM was estimated with new indices from the wetting curve for one side-coated specimen. For TSM, it was more effective to use Cu as a wetting layer with Au as a protection layer than to use Au as a wetting layer alone. The degree of wetting of Sn–5Sb and Sn–57Bi solder was better than that of Sn–37Pb and Sn–3.5Ag solder. However, the wetting rate of Sn–37Pb solder was higher than those of Pb-free solders. The wetting angle of TSM-coated glass substrate to solders could be calculated from the force balance equation by measuring static state force and tilt angle. The wetting angles of Cr/Cu/Au TSM to Sn–37Pb, Sn–3.5Ag, Sn–5Sb and Sn–57Bi were 69.4°, 67.2°, 60.1° and 53.0°, respectively.