Phase Field Modeling of Ghost Diffusion in Sn-Ag-Cu Solder Joints

In this paper, we have introduced a phase field modeling technique to simulate ghost diffusion phenomena of intermetallic compounds in a bulk metallic matrix phase. We used Zenner-Frank phase field approach to define free energy density functional which is to be evolved using Chan-Hilliard and Alan-Chan equations to simulate time evolution of the precipitates. We verified our simulation results with intermetallic compound growth of Sn-Ag-Cu solder joints in isothermal aging process attributing to the diffusion of Ag3Sn intermetallic compound. Herewith we present that Zenner-Frank model demonstrates sound validity and provides a best understanding of such phenomena.