Effect of Bi addition on the activation energy for the growth of Cu5Zn8 intermetallic in the Sn–Zn lead-free solder

Effects of current density on the formation and microstructure of Sn–9Zn, Sn–8Zn–3Bi and Sn–3Ag–0.5Cu solder joints

“…1(b) and (c), respectively. Based on the EDX results from previous works [9,27,34,35], the IMC layer in both systems had been identified as Cu 5 Zn 8 . The formation of the sharp interface is possibly due to the diffusion of Zn into the Cu substrate to form a supersaturated Cu 5 Zn 8 IMC.…”

“…The wettability of Sne9Zn, Sne8Zne3Bi and Sne3Age0.5Cu solder alloys [26], and the growth kinectisc of Cu 5 Zn 8 in the first two solder alloys during aging [27] have been investigated. Besides, the formation of voids and growth of Cu 5 Zn 8 in Sne8Zne3Bi by electromigration have been reported [9].…”

Investigation on the intermetallic compound layer growth of SnZnGa/SnZnGaNd solder joints

“…The activation energy of Cu 5 Zn 8 during aging is estimated to be 48.76 kJ/mol for SnZnGa/Cu solder joints and 56.99 kJ/mol for SnZnGa0.08Nd/Cu solder joints, which shows the Nd can increase the activation energy of Cu 5 Zn 8 growth of solder joints. Table 1 shows activation energies data from other works [14][15][16][17] Comparing the materials and experiments, the discrepancy among the activation energies is due to the differences in the solder materials, diffusion couple method, aging conditions (temperatures and times) and relative analytical method which were used. In addition, the rare earth Ce and Yb can also reduce the IMC thickness in lead-free solder joints [18,19].…”

A Study of Temperature, Microstructure and Hardness Properties of Sn-3.8Ag-0.7Cu (SAC) Solder Alloy

“…Though, a drawback of this solder is that it is harmful to humans [5,[12][13][14], prompting environmental regulations worldwide to eliminate its usage [15][16][17]. Some studies have suggested that among the lead-free alloys available, the Sn-Zn [18][19][20], Sn-Bi [21][22][23] and Sn-Cu [24,25] alloys are quite promising as replacements for lead-based solder. Unfortunately, the Sn-Cu holds higher melting temperatures of 237°C [26] and the Sn-Zn is prone to oxidation [20], while Sn-Bi is a low strength solder [21].…”

“…Some studies have suggested that among the lead-free alloys available, the Sn-Zn [18][19][20], Sn-Bi [21][22][23] and Sn-Cu [24,25] alloys are quite promising as replacements for lead-based solder. Unfortunately, the Sn-Cu holds higher melting temperatures of 237°C [26] and the Sn-Zn is prone to oxidation [20], while Sn-Bi is a low strength solder [21]. Few studies have then identified the Sn-Ag-Cu alloys as the most desirable candidates to replace lead-based solder.…”