Metallurgical analysis reveals Kirkendall pore formation during thermal aging in Cu-Au-Sn contacts, indicating that zeta-phase Au-Sn prevents copper diffusion and bond degradation.
Works done on different Au-Sn-Cu and Au-Cu metallurgies in the inner lead bond (ILB) area is summarized. The influence of Kirkendall pore formation in the Cu-Au-Sn system as a degradation mechanism is shown. This effect, together with the formation of new types of ternary intermetallic compounds, is observed during thermal aging in contacts with a direct interface between the eutectic 80/20 Au-Sn alloy and Cu. The zeta-phase (Au/Sn 90/10) acts like a diffusion barrier, which inhibits the pore formation associated with Cu diffusion. The composition of the ternary intermetallic compounds, their growth constant, and activation energy is determined. The possibilities to increase the contact reliability by producing a reliable Au-Sn metallurgy during the ILB process are shown.>
No takes yet. Share an insight, caveat, or question.
Zakel et al. (1993) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: