A Study on the Creep Characteristics of QFP Solder Joints

QFP 솔더접합부의 크립특성에 관한 연구

  • 조윤성 (중앙대학교 공과대학 기계공학부) ;
  • 최명기 (중앙대학교 공과대학 기계공학부) ;
  • 김종민 (중앙대학교 공과대학 기계공학부) ;
  • 이성혁 (중앙대학교 공과대학 기계공학부) ;
  • 신영의 (중앙대학교 공과대학 기계공학부)
  • Published : 2007.10.15

Abstract

In this paper, the creep characteristics of lead and lead-free solder joint were investigated using the QFP(Quad Flat Package) creep test. Two kind of solder pastes(Sn-3Ag-0.5Cu, Sn-0.2Sb-0.4Ag-37.4Pb) were applied to the QFP solder joints and each specimen was checked the external and internal failures(i.e., wetting failure, void, pin hole, poor-heel fillet) by digital microscope and X-ray inspection. The creep test was conducted at the temperatures of $100^{\circ}C$ and $130^{\circ}C$ under the load of 15$\sim$20% of average pull strength in solder joints. The creep characteristics of each solder joints were compared using the creep strain-time curve and creep strain rate-stress curves. Through the comparison, the Sn-3Ag-0.5Cu solder joints have higher creep resistance than that of Sn-0.3Sb-0.4Ag-37.4Pb. Also, the grain boundary sliding in the fracture surface and the necking of solder joint were observed by FE-SEM.

Keywords

References

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