Experiment Study on Reliability of Solder Joints under Electrical Stressing - Nano-indentation, Atomic Flux Measurement

摘要

The electromigration damage in flip chip solder joints of eutectic SnPb was studied under current stressing at room temperature with the current density about 1.3xl0~4A/cm~2. The diameter of the solder joints was about 140μm. The mass accumulation near anode side and void nucleation near cathode were observed during current stressing. The nano-indentation test was first time done on solder joints for electromigration test. Surface marker movement was used to measure the atomic flux driven by electromigration and to calculate the product of effective charge number and diffusivity, DXZ~*, of the solder at room temperature. The effective charge number can be extracted with the solder diffusivity at room temperature known.