Influence of dual ceramic nanomaterials on the solderability and interfacial reactions between lead-free Sn-Ag-Cu and a Cu conductor

This study examined the addition of dual ceramic nanomaterials, TiO₂ and graphene (0, 0.03, 0.12, 0.21, and 0.60 wt %), to a lead-free Sn-3.0 wt %Ag-0.5 wt %Cu (SAC305) solder alloy. TiO₂ and graphene nanomaterials were mixed simultaneously at equal weight fractions into the SAC305 molten solder by mechanical mixing and melting to produce a bulk nanocomposite solder. The effects of the dual nanomaterials on the melting point, microstructure, solderability, and intermetallic compound (IMC) growth were conducted. The structural and morphological features of the samples were characterized by field emission scanning electron microscopy, energy dispersive spectroscopy, and transmission electron microscopy. In addition, the melting behavior of the nanocomposite solder was characterized by differential scanning calorimetry. The nanocomposite solder with 0.21 wt % nanomaterials showed 33.67% enhancement in wettability and an 8.66% increase in spreadability due to the increased fluidity and decreased surface tension of molten solder in the presence of dual nanomaterials. In addition, the thickness of the IMCs was reduced after adding the dual nanomaterials to the monolithic SAC alloy. The optimal concentration of the dual nanomaterials in the monolithic SAC alloy was found to be 0.21 wt %.