Influence of Sb and Cu in Sn-Sb-Cu alloys on wetting of Cu and Cu-solder-Cu joint strength

Abstract

The influence of Sb (5, 10 and 20 at.%) and copper (0, 1.8, 3.4 and 3.7 at.%) in lead-free Sn-Sb-Cu solder on wetting of copper substrate at the temperature 623 K (350°C) in air using flux and in N2+10H 2 gas until 1800 s was studied by the sessile drop method. Wetting angle in air increases with the increase of Sb and Cu concentration in the solder whereas wetting in N2+10H2 practically does not depend on the Sb concentration. The influence of antimony and copper in Sn-Sb-Cu solder on the strength of Cu-solder-Cu joints prepared at the same conditions as wetting was also studied. Shear strength of the joints produced in air and in the gas mildly decreases with increasing amount of antimony and copper in both cases with the production of the joint in air as well as in the gas. The solidus and liquidus temperatures as well as heats of melting of all solders in ribbon and bulk shape were determined by differential scanning calorimetry (DSC) method.