|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Emerging Interconnect and Pb-free Materials for Advanced Packaging Technology
||Enhanced Stabilization of η Cu6Sn5 in Pb-free Solder Joints
||Takatoshi Nishimura, Mohd Salleh, Guang Zeng, Keith Sweatman, Stewart McDonald, Kazuhiro Nogita
|On-Site Speaker (Planned)
Stabilization by Ni of the hexagonal η form of Cu6Sn5 ensures the mechanical integrity of the intermetallic layer that forms between Pb-free solders and Cu substrates. The η–(Cu,Ni)6Sn5 also grows more slowly with a consequent reduced likelihood that Cu3Sn will form at the interface between the (Cu,Ni)6Sn5 and the Cu, another factor that can contribute to a reduction in the resistance to drop impact. It has been found that Zn behaves in a manner similar to Ni in stabilizing the η-Cu6Sn5 creating the possibility of providing an additional complementary stabilizing effect that would ensure that the stability of the η form could be maintained during extended service. In this paper the authors will report the results of high speed shear testing of reflowed solder spheres of Sn-0.7Cu with additions of Ni and Ni+Zn in both the as-soldered condition and after extended ageing at 150°C.
||Planned: A print-only volume