Leaching of heavy metal elements in solder alloys

Corrosion and Leaching Behaviours of Sn-0.7Cu-0.05Ni Lead-Free Solder in 3.5 wt.% NaCl Solution

“…When compared with the XRD results of Yan and Xian [28] peaks for tin hydroxide (Sn(OH 2 )) were also observed particularly for Sn-Pb and Sn metal [25]. These oxides effectively protect the metal.…”

“…Formation of tin oxides is thermodynamically favourable thus tin hydroxides can dehydrate easily to form SnO and SnO 2 [25,29]. Although not detected in XRD due to its trace concentration relative to Sn, the potential corrosion products 6 International Journal of Corrosion …”

“…The amount of Sn leached correlates with the corrosion rate of the alloys [25,29,34]. Since the results of potentiodynamic polarization test showed that all of the three Pb-free solders had higher corrosion rate than the Sn-Pb solder and Sn metal, leaching amounts of Sn were done only for the Pb-free solders.…”

“…For the leaching/dissolution measurement, the method by Cheng et al [25] was adopted with slight modification. Small test cells containing 15 mL of test solutions were placed in a temperature-controlled oil bath at 45 ± 3 ∘ C. Every 3 days, oxygen was injected into the test solutions by gas flowmeter with a flow rate of 46 mL/min for 5 mins to keep the solution under low saturation of oxygen.…”

Effect of Corrosion on Mechanical Reliability of Sn-Ag Flip-Chip Solder Joint

“…Some researchers have studied the corrosion behaviors of conventional Sn-Pb solders and Pb-free solder alloys such as Sn-Ag, Sn-Ag-Cu, Sn-Cu and Sn-Zn. [14][15][16][17][18][19][20][21][22][23] However, few studies have been conducted on the corrosion behavior of the Sn-Ag ip-chip solder bump and the corresponding bump mechanical reliability. The objective of this study was to evaluate the effect of corrosion on the bump shear strength and failure behavior (fracture mode).…”