Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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Effect of Multiple Reflows on Mechanical and Electrical Properties of ENIG/Sn-3.5Ag/ENIG Ball Grid Array (BGA) Solder Joint

리플로우 횟수가 ENIG/Sn-3.5Ag/ENIG BGA 솔더 조인트의 기계적, 전기적 특성에 미치는 영향

  • Sung, Ji-Yoon (School of Advanced Materials Science & Engineering, Sungkyunkwan University) ;
  • Pyo, Sung-Eun (School of Advanced Materials Science & Engineering, Sungkyunkwan University) ;
  • Koo, Ja-Myeong (SAMSUNG ELECTRONICS CO.,LTD) ;
  • Yoon, Jeong-Won (School of Advanced Materials Science & Engineering, Sungkyunkwan University) ;
  • Noh, Bo-In (School of Advanced Materials Science & Engineering, Sungkyunkwan University) ;
  • Won, Sung-Ho (Department of applied chemistry, DongYang Technical College) ;
  • Jung, Seung-Boo (School of Advanced Materials Science & Engineering, Sungkyunkwan University)
  • 성지윤 (성균관대학교 신소재공학부) ;
  • 표성은 (성균관대학교 신소재공학부) ;
  • 구자명 (삼성전자 주식회사) ;
  • 윤정원 (성균관대학교 신소재공학부) ;
  • 노보인 (성균관대학교 신소재공학부) ;
  • 원성호 (동양공업전문대학교 응용화학과) ;
  • 정승부 (성균관대학교 신소재공학부)
  • Published : 2009.03.30
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Abstract

In this study, solder joints were made with Sn-3.5Ag (wt%) solder ball. Electroless nickel / immersion gold (ENIG) printed circuit board (PCB) substrates were employed in this work. The mechanical and electrical properties were measured as a function of the number of reflow. Die shear strength was measured with increasing reflow number. Until the forth or fifth reflow, shear force increased and after the fifth reflow the shear force of die decreased. The electrical resistivity of solder joint linearly increased with increasing reflow number.

본 연구에서는 electroless nickel / immersion gold (ENIG) 처리된 printed circuit board (PCB)를 무연 솔더인 Sn-3.5(wt%)Ag로 접합하였다. 리플로우 횟수를 1회부터 10회까지 다양하게 하여 리플로우 횟수가 증가함에 따른 솔더 접합부의 기계적, 전기적 특성의 변화에 대해 연구하였다. 접합부의 미세 조직 관찰을 위해 접합부 단면을 폴리싱 하여 금속간 화합물의 두께를 측정하고 종류를 분석하였다. 접합부의 기계적 특성을 평가하기 위해서 die 전단 시험을 하였는데, 리플로우 횟수가 4-5회일 때까지 전단 강도 값이 증가하다가 5회 이후로 감소하였다. 전기적 특성을 알아보기 위해 전기 저항 값을 측정하였는데, 리플로우 횟수가 증가할수록 접합부의 전기 저항 값은 점점 증가하였다.

Keywords

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