Electromigration and Thermomigration in Flip-Chip Joints in a High Wiring Density Semiconductor Package

• 발행기관: 한국마이크로전자및패키징학회
• 저자명: Kimihiro Yamanaka
• 간행물 정보: 『마이크로전자 및 패키징학회지』제18권 제3호, 67~74쪽, 전체 8쪽
• 주제분류: 공학 > 산업공학
• 파일형태: PDF
• 발행일자: 2011.09.30

영문 초록

Keys to high wiring density semiconductor packages include flip-chip bonding and build-up substrate technologies. The current issues are the establishment of a fine pitch flip-chip bonding technology and a low coefficient of thermal expansion (CTE) substrate technology. In particular, electromigration and thermomigration in fine pitch flipchip joints have been recognized as a major reliability issue. In this paper, electromigration and thermomigration in Cu/Sn-3Ag-0.5Cu (SAC305) /Cu flip-chip joints and electromigration in Cu/In/Cu flip chip joints are investigated. In the electromigration test, a large electromigration void nucleation at the cathode, large growth of intermetallic compounds (IMCs) at the anode, a unique solder bump deformation towards the cathode, and the significantly prolonged electromigration lifetime with the underfill were observed in both types of joints. In addition, the effects of crystallographic orientation of Sn on electromigration were observed in the Cu/SAC305/Cu joints. In the thermomigration test, Cu dissolution was accelerated on the hot side, and formation of IMCs was enhanced on the cold side at a thermal gradient of about 60℃/cm, which was lower than previously reported. The rate of Cu atom migration was found comparable to that of electromigration under current conditions.

목차

1. Introduction

2. Experimental method

3. Results and discussion

4. Conclusions

Acknowledgments

References

키워드

EM Flip-Chip diffusion reliability