Journal of the Korean institute of surface engineering (한국표면공학회지)

The Korean Institute of Surface Engineering (한국표면공학회)
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The Stability of Plating Solution and the Current Density Characteristics of the Sn-Ag Plating for the Wafer Bumping

  • Received : 2017.04.13
  • Accepted : 2017.06.27
  • Published : 2017.06.30
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Abstract

In this study, the effects of the concentration of metal ions and the applied current density in the Sn-Ag plating solutions were examined in regards to the resulting composition and morphology of the solder bumps' surface. Furthermore the effect of any impurities present in the methanesulfonic acid used as a base acid in the Sn-Ag solder plating solution on the stability of plating solution as well as the characteristics of the Sn-Ag alloys films was also explored. As expected, the uniform bump was obtained by means of removing impurities in the plating solution. Consequently the resultant solder bump was obtained in an optimal current density of the range of $1A/dm^2$ to $15A/dm^2$, which has acceptable bump shape and surface roughness with 12inch wafer trial results.

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References

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