The Simulation and Analysis of Current Crowding and Joule Heat in Flip Chip Solder Bumps

Abstract:

Electro-migration has become a critical reliability issue for high density solder joints in flip chip technology, especially for current crowding and joule heat. Electro-migration force and mean time to failure of flip chip are introduced in this paper. This study employs two-dimensional simulation to investigate the distribution of current density and Joule heating in the flip chip joint. It is found that current crowding and Joule heat effect are very serious in the solder bump. The Joule heat may play important role in the void formation and thermo-migration in solder bump. And the factors that impact the distribution of current density and Joule heat are studied. The results show that the thickness of Al and UBM has great influence on the distribution of current density and Joule heat.

• Periodical: Key Engineering Materials (Volumes 645-646)
• Pages: 319-324
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.645-646.319
• Online since: May 2015
• Authors: Pei Sheng Liu*, Long Long Yang, Jin Xin Hang, Ying Lu
• Keywords: Current Density, Finite Element Analysis, Flip Chip, Joule Heat, Reliability

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