ABSTRACT
Tin-lead is used as the primary electronic interconnection material in solder pastes, PCB coatings, and as a finish on the external leads of electronic components such as surface-mount and through-hole devices, or as a solder ball or bumpmaterial on advanced semiconductor packages, such as ball grid arrays (BGAs), chip scale packages (CSPs), and flip-chip devices. In order to create a truly environmentally safe Pb-free electronic assembly it is required that Pb-free materials be used throughout the interconnection. As with solder pastes, many options exist for creating a Pb-free circuit board or component finish.
