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Flip-Chip Underfill: Materials, Process, and Reliability

  • Zhuqing ZhangEmail author
  • Pengli Zhu
  • 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 thermo-mechanical 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 material and has many disadvantages. In order to overcome these disadvantages, many variations have been invented to improve the flip-chip underfill process. This chapter 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

Flip-chip Underfill Molded underfill 3D stacks Materials Reliability Coefficient of thermal expansion 

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Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  1. 1.HP Inc.CorvallisUSA
  2. 2.Shenzhen Institutes of Advanced Technology, Chinese Academy of SciencesShenzhenChina
  3. 3.Georgia Institute of TechnologyAtlantaUSA

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