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Flip Chip Underfill: Materials, Process, and Reliability

  • Zhuqing Zhang
  • Shijian Luo
  • C. P. Wong
Chapter

Abstract

In order to enhance the reliability of a flip chip on organic board package, underfill is usually used to redistribute the thermomechanical stress created by the Coefficient of Thermal Expansion (CTE) mismatch between the silicon chip and organic substrate. However, the conventional underfill relies on the capillary flow of the underfill resin and has many disadvantages. In order to overcome these disadvantages, many variations have been invented to improve the flip chip underfill process. This paper reviews the recent advances in the material design, process development, and reliability issues of flip chip underfill, especially in no-flow underfill, molded underfill, and wafer-level underfill. The relationship between the materials, process, and reliability in these packages is discussed.

Keywords

Solder Joint Adhesion Strength Solder Bump Silane Coupling Agent Flip Chip 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Hewlett-Packard CompanyCorvallisUSA
  2. 2.Micron Technology, Inc.BoiseUSA
  3. 3.The Chinese University of Hong KongShatin, NTHong Kong, SAR
  4. 4.Georgia Institute of Technology School of Materials Science & EngineeringAtlantaUSA

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