Online ISSN : 1347-5320
Print ISSN : 1345-9678
ISSN-L : 1345-9678
Effect of Addition of Small Amount of Zinc on Microstructural Evolution and Thermal Shock Behavior in Low-Ag Sn–Ag–Cu Solder Joints during Thermal Cycling
Naoyuki HamadaTokuteru UesugiYorinobu TakigawaKenji Higashi
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2013 Volume 54 Issue 5 Pages 796-805


The effects of adding small amounts of Zn on the microstructural evolution of low-Ag Sn–Ag–Cu solders and thermal shock behavior during thermal cycling between −40 and 125°C were investigated. Observation of the visual appearance of the solder joints revealed that the probability of solder deformation and crack initiation in the solder fillets after thermal cycling was lower in Sn–1Ag–0.3Cu–1Zn than in Sn–3Ag–0.5Cu. Microstructural observation of the interface of the solder joints revealed that the addition of Zn to a low-Ag Sn–Ag–Cu solder inhibited the growth of the intermetallic compound layer between the solder and the Cu pad in printed circuit boards. The addition of small amounts of Zn improved the thermal shock behavior of the low-Ag Sn–Ag–Cu solder.

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© 2013 The Japan Institute of Metals and Materials
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