Evaluation on Reliability of High Temperature Lead-free Solder for Automotive Electronics

자동차 전장 보드용 고온 무연 솔더의 신뢰성 평가

  • Ko, Yong-Ho (Advanced Welding & Joining Technology Center, Korea Institute of Industrial Technology) ;
  • Yoo, Se-Hoon (Advanced Welding & Joining Technology Center, Korea Institute of Industrial Technology) ;
  • Lee, Chang-Woo (Advanced Welding & Joining Technology Center, Korea Institute of Industrial Technology)
  • 고용호 (한국생산기술연구원 용접접합기술센터) ;
  • 유세훈 (한국생산기술연구원 용접접합기술센터) ;
  • 이창우 (한국생산기술연구원 용접접합기술센터)
  • Received : 2010.09.14
  • Accepted : 2010.11.15
  • Published : 2010.12.30

Abstract

In this study, the reliability of thermal shock, thermal cycle, and complex vibration test at high temperature were examined for 3 types of lead-free solder alloys, Sn-3.5Ag, Sn-0.7Cu and Sn-5.0Sb. For the reliability test, daisychained BGA chips with ENIG-finished Cu pad was assembled with the three lead-free solders on OSP-finished PCBs. Among the 3 types solder alloys, Sn-3.5Ag solder alloy showed the highest degradation rate of electrical resistance and joint strength. On the other hand, Sn-0.7Cu solder alloy had high stability after the reliability tests.

본 연구에서는 상용 고온 솔더 중 많이 쓰이고 있는 Sn-3.5Ag, Sn-0.7Cu, Sn-5.0Sb 솔더에 대한 열충격 시험, 열싸이클 시험, 고온 진동 복합 시험 신뢰성 평가를 하였다. 테스트 샘플을 제작하기 위해 Sn-3.5Ag, Sn-0.7Cu, Sn-5.0Sb 솔더볼을 ENIG 표면 처리된 BGA에 접합하였으며, 그 후 BGA샘플을 OSP 표면 처리된 PCB에 실장 하였다. 신뢰성평가 동안 저항변화를 측정하였으며 신뢰성 평가 전후 전단강도 시험을 통하여 접합강도의 변화를 평가하였다. Sn-3.5Ag의 솔더인 경우 전기저항과 접합강도의 저하가 비교 평가한 3가지 솔더 중 가장 높은 저하율을 보였으며 Sn-0.7Cu의 솔더가 신뢰성 평가 후에 비교적 높은 안정성을 나타내었다.

Keywords

References

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