The impact of implementing a Pb-free manufacturing production process
Legislation in Europe (RoHS) requires the implementation of Pb-free products by June of 2006. Electronic Industry groups have evaluated several of these lead-free materials and have chosen the Sn/Ag/Cu alloy as a short to mid-term solution. The typical alloy composition is Sn96.5Ag3.0Cu0.5 (called SAC305) and reflows at a temperature of 217
A second concern with implementing a Pb-free soldering process is the qualification of a Pb-free solder paste. There are two major concerns with the implementation of a Pb-free solder paste: 1) solder paste print performance and 2) reflow characteristics. The solder paste should behave no differently than a SnPb solder paste and be capable of handling a very large process window. Ideally, an assembly manufacturer would like to have a solder paste that is capable of reflowing at very low temperatures (230