Interfacial Reaction Characteristics of a Bi-20Sb-10Cu-0.3Ni Pb-free Solder Alloy on Cu Pad

Bi-10Cu-20Sb-0.3Ni 고온용 무연 솔더와 Cu와의 계면 반응 특성

  • Kim, Ju-Hyung (Department of Materials Science & Engineering, Seoul National University of Technology) ;
  • Hyun, Chang-Yong (Department of Materials Science & Engineering, Seoul National University of Technology) ;
  • Lee, Jong-Hyun (Department of Materials Science & Engineering, Seoul National University of Technology)
  • 김주형 (서울산업대학교 신소재공학과) ;
  • 현창용 (서울산업대학교 신소재공학과) ;
  • 이종현 (서울산업대학교 신소재공학과)
  • Received : 2010.02.05
  • Accepted : 2010.02.25
  • Published : 2010.03.30

Abstract

Interfacial reaction characteristics of a Bi-10Cu-20Sb-0.3Ni Pb-free alloy on Cu pad was investigated by reflow soldering at $430^{\circ}C$. The thickness of interfacial reaction layers with respect to the soldering time was also measured. After the reflow soldering, it was observed that a $(Cu,Ni)_2Sb$, a $Cu_4Sb$ intermetallic layer, and a haze layer, which is consisted of Bi and $Cu_4Sb$ phases, were successively formed at the Bi-10Cu-20Sb-0.3Ni/Cu interface. The total thickness of the reaction layers was found to be linearly increased with increasing of the reflow soldering time up to 120 s. As the added Ni element did not participate in the formation of the thickest $Cu_4Sb$ interfacial layer, suppression of the interfacial growth was not observed.

본 연구에서는 $430^{\circ}C$에서 Bi-10Cu-20Sb-0.3Ni 조성의 솔더 합금과 Cu간의 리플로루 솔더링 시 생성되는 계면 반응층을 분석하였고, 솔더링 시간에 따른 계면 반응층의 성장 속도를 측정하였다. 리플로우 솔더링 후 Bi-10Cu-20Sb-0.3Ni/Cu의 계면 반응층을 분석한 결과, $(Cu,Ni)_2Sb$$Cu_4Sb$ 금속간 화합물층, 그리고 Bi 조성과 $Cu_4Sb$ 상이 주기적으로 존재하는 아지랑이 형상층이 연속적으로 생성되었다. 또한 120 s까지의 솔더링 시간 영역에서는 계면 반응층의 총 두께가 솔더링 시간에 대해 직선적으로 증가하는 경향이 관찰되었다. 합금원소로 첨가된 Ni은 가장 두꺼운 $Cu_4Sb$ 반응층의 형성에 참여하지 않아 계면 금속간 화합물의 성장 속도를 억제시키는 작용을 나타내지 못했다.

Keywords

References

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