The Interaction of Sn-Zn-Al Solder with Copper and ENIG Substrates-(PPT)

摘要

The Sn-Zn eutectic alloy constitutes a potential Pb-free replacement for eutectic Pb-Sn with a melting point of 199°C. However, excessive oxidation of the Zn component of this alloy has been considered a serious impediment to its use. It has been found that the addition of a small quantity of Al will prevent excessive Zn oxidation in the liquid solder. Solders such as the Sn-7wt% Zn-60 ppm Al alloy have been used successfully in the manufacture of a number of commercial electronic devices.