Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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Effect of PCB Surface Finishs on Intermetallic Compound Growth Kinetics of Sn-3.0Ag-0.5Cu Solder Bump

Sn-3.0Ag-0.5Cu 솔더범프의 금속간화합물 성장거동에 미치는 PCB 표면처리의 영향

  • Jeong, Myeong-Hyeok (School of Materials Science and Engineering, Andong National University) ;
  • Kim, Jae-Myeong (School of Materials Science and Engineering, Andong National University) ;
  • Yoo, Se-Hoon (Korea Institute of Industrial Technology, Micro-Joining Center) ;
  • Lee, Chang-Woo (Korea Institute of Industrial Technology, Micro-Joining Center) ;
  • Park, Young-Bae (School of Materials Science and Engineering, Andong National University)
  • 정명혁 (안동대학교 신소재공학부 청정소재기술연구센터) ;
  • 김재명 (안동대학교 신소재공학부 청정소재기술연구센터) ;
  • 유세훈 (한국생산기술연구원 마이크로조이닝 산학연사업단) ;
  • 이창우 (한국생산기술연구원 마이크로조이닝 산학연사업단) ;
  • 박영배 (안동대학교 신소재공학부 청정소재기술연구센터)
  • Received : 2010.02.23
  • Accepted : 2010.03.28
  • Published : 2010.03.30
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Abstract

Thermal annealing and electromigration test were performed at $150^{\circ}C$ and $4{\times}10^3\;A/cm^2$ conditions in order to investigate the effect of PCB surface finishs on the growth kinetics of intermetallic compound (IMC) in Sn-3.0Ag-0.5Cu solder bump. The surface finishes of the electrodes of printed circuit board (PCB) were organic solderability preservation (OSP), immersion Sn, and electroless Ni/immersion gold (ENIG). During thermal annealing, the OSP and immersion Sn show similar IMC growth velocity, while ENIG surface finish had much slower IMC growth velocity. Applying electric current accelerated IMC growth velocity and showed polarity effect due to directional electron flow.

Sn-3.0Ag-0.5Cu 솔더범프의 금속간화합물 성장거동에 미치는 PCB 표면처리의 영향을 알아보기 위해서 PCB 패드 표면에 각각 OSP, immersion Sn, 그리고 ENIG를 처리하였고, 열처리는 $150^{\circ}C$ 조건에서 실험을 실시하였다. 또한, 전류인가시 Sn-3.0Ag-0.5Cu 솔더범프의 접합부 계면반응에 미치는 표면처리의 영향을 알아보기 위해서 $150^{\circ}C$, $4{\times}10^3\;A/cm^2$ 조건에서 electromigration특성을 비교 평가하였다. 열처리시 OSP와 immersion Sn의 금속간화합물 성장거동은 서로 비슷한 경향을 보인 반면, ENIG는 다른 표면처리에 비해 훨씬 느린 성장거동을 보였다. electromigration특성 평가결과 열처리에 비해 금속간화합물의 성장이 가속화되나 표면처리별 경향은 유사하였고, 전자 이동 방향에 따른 음극-양극에서 금속간화합물 형성의 차이를 보이는 극성효과(polarity effect)가 나타나는 것을 알 수 있었다.

Keywords

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