About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Electronic Packaging and Interconnection
|
Presentation Title |
Kinetics of the Accumulation of Bismuth at the Anode of a Sn-Bi Based Solder Joint during Current Stressing |
Author(s) |
Eric J. Cotts, Faramarz Hadian, Javier Flores, Sitaram Panta, Mohammed Genanu |
On-Site Speaker (Planned) |
Eric J. Cotts |
Abstract Scope |
The evolution of the microstructure of SnBi-based solder joints during current stressing was examined using scanning electron microscopy, and in-situ measurements of electrical resistance. A Bi layer was observed to accumulate at the anode at a linear rate. A correlated increase in the electrical resistance was observed (eventually exceeding the standard JEDEC failure criteria of twenty percent). An expression for the rate of increase of the thickness of the Bi layer was generated from simple diffusion theory, and fit to the data at temperatures between 60 and 125oC, and current densities between 2,000 and 9,000 A/cm2. This expression was related to a specific form of Black's equation for mean time to failure (one inversely proportional to current density, with an apparent activation energy of 1 eV), that produced a good fit to the data for failure times. |
Proceedings Inclusion? |
Planned: |
Keywords |
Electronic Materials, Modeling and Simulation, Characterization |