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Intermetallic compounds in 3D integrated circuits technology: a brief review.
Syahira Annuar1, Reza Mahmoodian1,2,3, Mohd Hamdi1,2
1Centre for advanced manufacturing and materials processing (AMMP), Department of Mechanical Engineering, Faculty of Engineering, University of Malaya, Kuala Lumpur, Malaysia.
Science and Technology of Advanced Materials
|October 24, 2017
Summary
Pb-free solder microbumps in 3D-ICs offer environmental benefits but face reliability challenges. Excessive intermetallic compounds (IMCs) formation and embrittlement are key concerns for these advanced microelectronic devices.
Area of Science:
- Materials Science
- Microelectronics Engineering
- Reliability Engineering
Background:
- Three-dimensional integrated circuits (3D-ICs) are crucial for high-performance, miniaturized mobile electronics.
- Chip stacking using through-Si-via and solder microbumps is a key enabling technology for 3D-ICs.
- Environmental concerns drive the adoption of lead-free (Pb-free) solder microbumps over traditional lead-containing solder joints.
Purpose of the Study:
- To review current technologies for 3D-ICs.
- To examine the mechanisms of intermetallic compounds (IMCs) formation in Pb-free solder microbumps.
- To discuss the reliability challenges associated with IMCs growth in Pb-free solder microbumps for 3D-ICs.
Main Methods:
- Literature review of 3D-IC technologies.
- Analysis of IMC formation mechanisms in Pb-free solder systems.
- Evaluation of reliability issues stemming from IMCs in microelectronic packaging.
Main Results:
- Pb-free solder microbumps, while environmentally friendly, are prone to excessive IMC formation.
- IMCs growth can lead to solder microbump embrittlement, compromising device reliability.
- The low-volume nature of microbumps exacerbates these reliability concerns.
Conclusions:
- Reliability issues related to IMCs in Pb-free solder microbumps are critical for the advancement of 3D-ICs.
- Further research is needed to mitigate IMC formation and improve the long-term reliability of these components.
- The future outlook suggests significant research growth in addressing these challenges for sustainable microelectronics.
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