At present, there is common consensus from both the industry and the academia that Sn-Ag-Cu alloys will be the primary material for Lead Free solders in the future.

Nevertheless, this Sn-Ag-Cu alloy still causes production problems and defects in assembly practices; for instance:

Because the Spread and Wetting properties of Sn-Ag-Cu are not as desirable as Sn63/Pb37 alloy's, it is common to supply with inert gas (nitrogen) to prevent oxidation when re-flowing, which results in De-wetting in SMT assembly process.

In Wave Soldering, the residue produced from Sn-Ag-Cu alloy is much higher than from