We have studied the effects of Ag on the characteristics of Sn43Bi57Agx(wt%) lead-free solders for photovoltaic ribbon. Ag atoms in the solder formed an alloy phase of Ag3Sn after reacting with some part of Sn atoms, while they did not react with Bi atoms, but decreased the mean size of Bi solid phase and the thickness of solder. When Ag atoms of 3.0 wt% was added to eutectic Sn43Bi57(wt%) solder, it showed the optimally useful results that the peel strength of photovoltaic ribbon greatly increased and the sheet resistance of the solder decreased. In the meanwhile, the eutectic Sn43Bi57(wt%) solder showed a low melting temperature of 138.9℃, and showed a very similar result regardless of the added amount of Ag atoms.
