Abstract
In this paper, the effect of the stand-off height (SOH) on the microstructure and tensile strength of Cu/Sn-8Zn-3Bi/Cu and Cu/Sn-9Zn/Cu solder joints with SOH of 100µm, 50µm, 20µm and 10µm were studied. The results show that as the SOH is reduced, the needle-like Zn-rich phase steadily decrease until completely disappeared in both of the two solder joints. For Cu/Sn-9Zn/Cu, Cu 5 Zn 8 IMC is formed, while, for Cu/Sn-8Zn-3Bi/Cu, two IMC layers are formed, the first layer adjacent to the Cu substrate is a flat Cu5Zn8 phase, and the second layer adjacent to the solder bulk is a mixture of Cu-Sn + Cu-Zn. In Cu/Sn-9Zn/Cu solder joints, the dissociative Cu 5 Zn 8 intermetallic compound (IMC) increases with the reduced SOH, while there are less dissociative IMCs found in the Cu/Sn-8Zn-3Bi/Cu solder joints. Bi dissolves into the solder bulk and does not participate in the interfacial reaction. Due to the addition of Bi, the tensile strength of the Cu/Sn8Zn3Bi/Cu solder joint is higher than that of the Cu/Sn9Zn/Cu solder joint. From the results of the tensile test, it is found that the ultimate tensile strength (UTS) of Cu/Sn-9Zn/Cu solder joints is decreased with the reduced SOH, while for Cu/Sn-8Zn-3Bi/Cu solder joints the UTS is increased.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
