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Bonding Property and Reliability for Press-fit Interconnection

Press-fit 단자 접합특성 및 신뢰성

  • Oh, Sangjoo (Electronic Convergence Material & Device Research Center, Korea Electronics Technology Institute) ;
  • Kim, Dajung (Electronic Convergence Material & Device Research Center, Korea Electronics Technology Institute) ;
  • Hong, Won Sik (Electronic Convergence Material & Device Research Center, Korea Electronics Technology Institute) ;
  • Oh, Chulmin (Electronic Convergence Material & Device Research Center, Korea Electronics Technology Institute)
  • 오상주 (전자부품연구원 융복합전자소재연구센터) ;
  • 김다정 (전자부품연구원 융복합전자소재연구센터) ;
  • 홍원식 (전자부품연구원 융복합전자소재연구센터) ;
  • 오철민 (전자부품연구원 융복합전자소재연구센터)
  • Received : 2019.08.29
  • Accepted : 2019.09.27
  • Published : 2019.09.30

Abstract

Soldering technology has been used in electronic industry for a long time. However, due to solder fatigue characteristics, automotive electronics are searching the semi-permanent interconnection technology such as press-fit method. Press fit interconnection is a joining technology that mechanically inserts a press fit metal terminal into a through hole in a board, and induces a strong bonding by closely contacting the inner surface joining of the through hole by plastic deformation of press-fit terminal. In this paper, the bonding properties of press-fit interconnection are investigated with PCB hole size and surface finishes. In order to compare interconnection reliability between the press fit and soldering, the change in resistance of the press-fit and soldering joints was observed during thermal shock test. After thermal cycling, the failure modes are investigated to reveal the degradation mechanism both press-fit and soldering technology.

전자부품에 대한 보드실장은 아직까지 솔더를 이용한 접합기술을 주로 이용하고 있다. 그러나, 솔더의 크? 및 피로특성으로 인한 접합부 내구한계로, 자동차 전장모듈에서는 반영구적인 접합기술인 프레스 핏(Press-fit) 접합기술 적용을 확대하고 있다. 프레스 핏 접합은 프레스 핏 금속단자를 보드내 쓰루 홀(Through hole)에 기계적으로 삽입하여 체결하는 접합기술로써, 적절한 금속단자의 소성변형으로 쓰루 홀 내부 표면접합을 밀착시킴으로써 강건한 접합을 유도한다. 본 논문에서는 보드내 쓰루 홀 크기 및 표면처리에 따른 프레스 핏 접합 특성 및 신뢰성을 솔더링과 함께 비교하기 위해, 보드 쓰루 홀 크기에 따른 삽입강도 및 삽발강도를 평가하였으며, 열충격 시험을 통한 실시간 저항변화를 통해 프레스 핏 및 솔더링 접합부의 저항변화를 관찰하였다. 또한, 각 접합부위 분석을 통한 프레스 핏 및 솔더링 접합열화를 분석하여 주요 파손모드를 고찰하고자 하였다.

Keywords

References

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