The effect of Ga content on the wetting reaction and interfacial morphology formed between Sn–8.55Zn–0.5Ag–0.1Al–xGa solders and Cu

The wetting properties of Sn–8.5Zn–0.5Ag–0.1Al–xGa lead-free solders were investigated. The wetting time and wetting angle decreased while the wetting force increased with the increase in Ga content. The intermetallic compounds were Al4.2Cu3.2Zn0.7, Cu5Zn8, Cu5Zn8 and AgZn3 in the solder. The activation energy and the surface tension of the solder were estimated.