Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
권호 표지
DOI QR코드

DOI QR Code

Effects of PCB Surface Finishes on Mechanical Reliability of Sn-1.2Ag-0.7Cu-0.4In Pb-free Solder Joint

PCB 표면처리에 따른 Sn-1.2Ag-0.7Cu-0.4In 무연솔더 접합부의 기계적 신뢰성에 관한 연구

  • Kim, Sung-Hyuk (School of Materials Science and Engineering, Andong National University) ;
  • Kim, Jae-Myeong (School of Materials Science and Engineering, Andong National University) ;
  • Yoo, Sehoon (Micro-Joining Center, Korea Institute of Industrial Technology) ;
  • Park, Young-Bae (School of Materials Science and Engineering, Andong National University)
  • 김성혁 (안동대학교 신소재공학부 청정에너지소재기술연구센터) ;
  • 김재명 (안동대학교 신소재공학부 청정에너지소재기술연구센터) ;
  • 유세훈 (한국생산기술연구원 마이크로조이닝 산학연사업단) ;
  • 박영배 (안동대학교 신소재공학부 청정에너지소재기술연구센터)
  • Received : 2012.12.04
  • Accepted : 2012.12.28
  • Published : 2012.12.30
Download PDF
⟨ Previous Next ⟩

Abstract

Ball shear test was performed by test variables such as loading speed and annealing time in order to investigate the effect of surface finishes on the bonding strength of Sn-1.2Ag-0.7Cu-0.4In Pb-free solder. The shear strength increased and the ductility decreased with increasing shear speed. With increasing shear speed, the electroless nickel immersion gold (ENIG) finish showed dominant brittle fracture mode, while organic solderability preservative (OSP) finish showed pad open fracture mode. The shear strength and toughness for both surface finishes decreased with increasing annealing time under the high-speed shear test of 500 mm/s. Typically, the thickness of intermetallic compound increased with increasing annealing time, which means that exposure of brittle fracture became much easier. With increasing annealing time, the both ENIG and OSP finishes exhibited the pad open fracture mode. Overall, ENIG finish showed higher shear strength rather than OSP finish due to its superior barrier stability.

표면처리에 따른 Sn-1.2Ag-0.7Cu-0.4In 솔더범프의 접합 강도 평가를 위하여 전단 속도 및 열처리 시간에 따른 볼 전단강도 시험을 실시하였다. 전반적으로, 전단속도가 증가함에 따라 전단강도는 증가하였지만 인성은 감소하는 경향을 나타내었다. 파괴모드 관찰 결과, 전단 속도가 증가함에 따라 파괴모드의 경우, ENIG(electroless nickel immersion gold) 처리는 취성파괴가 대부분 지배적으로 존재하였고, OSP(organic solderability preservative) 처리는 pad open이 주로 발생하였다. 또한, 500 mm/s의 고속전단시험에서는 열처리 시간이 증가함에 따라 표면처리별 전단강도와 인성 값 모두 감소하는 경향을 보였다. ENIG 표면처리가 OSP 표면처리 보다 좋은 접합강도 특성을 보이는 것은 솔더범프 계면의 금속간화합물의 물성 및 두께와 밀접한 연관이 있는 것으로 판단된다.

Keywords

References

  1. Directive 2002/95/EC on the Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment (RoHS), The European Parliament and of the Council of the European Union, Jan. (2003).
  2. European Union WEEE Directive, 3rd Draft, May (2000).
  3. D. Suh, D. W. Kim, P. Liu, H. Kim, J. A. Weninger, C. M. Kumar, A. Prasad, B. W. Grimsley and H. B. Tejada, "Effects of Ag Content on Fracture Resistance of Sn-Ag-Cu Lead-Free Solders under High-Strain Rate Conditions", Mater. Sci. Eng. A., 460, 595 (2007). https://doi.org/10.1016/j.msea.2007.01.145
  4. D. G. Kim, J. W. Kim, S. S. Ha, B. I. Noh, J. M. Koo, D. W. Park, M. W. Ko and S. B. Jung, "Effect of Reflow Numbers on the Interfacial Reaction and Shear Strength of Flip- Chip Solder Joints", J. Alloys Compd., 458(1), 253 (2007).
  5. M. Amagai, Y. Toyata and T. Tajima, "High Solder Joint Reliability with Lead-Free Solders", 53rd Electronic Components and Technology Conference (ECTC), New Orleans, 317, IEEE Components, Packaging and Manufacturing Technology Society (CPMT) (2003).
  6. D. Q. Yu, J. Zhao and L. Wang, "Improvement on the Microstructure Stability, Mechanical and Wetting Properties of Sn- Ag-Cu Lead-Free Solder with the Addition of Rare Earth Elements", J. Alloys Compd., 376(1), 170 (2004). https://doi.org/10.1016/j.jallcom.2004.01.012
  7. K. S. Kim, S. H. Huh and K. Suganuma, "Effects of Fourth Alloying Additive on Microstructures and Tensile Properties of Sn-Ag-Cu Alloy and Joints with Cu", Microelectron. Reliab., 43(2), 259 (2003). https://doi.org/10.1016/S0026-2714(02)00239-1
  8. S. K. Kang, P. A. Lauro, D. Y. Shih, D. W. Henderson and K. J. Puttlitz, "Microstructure and Mechanical Properties of Lead-Free Solders and Solder Joints Used in Microelectronic Applications", IBM J. Res. Dev., 49(4), 607 (2005). https://doi.org/10.1147/rd.494.0607
  9. J. M. Koo, C. Y. Lee and S. B. Jung, "Effect of Reflow Number on Mechanical and Electrical Properties of Ball Grid Array (BGA) Solder Joints", J. Microelectron. Packag. Soc., 14(4), 71 (2007).
  10. V. Denis and C. Gilles, "OSP Coatings: The Nitrogen Solution", Proc. 18th Electronic Manufacturing Technology Symposium, Austin, 101, IEEE Components, Packaging and Manufacturing Technology Society (CPMT) (1995).
  11. D. Chang, F. Bai, Y. P. Wang and C.S. Hsiao, "The Study of OSP as Reliable Surface Finish of BGA Substrate", Proc. 6th Electronics Packaging Technology Conference (EPTC), Singapore, 149, IEEE Components, Packaging and Manufacturing Technology Society (CPMT) (2004).
  12. H. K. Lee, S. H. Son, H. Y. Lee and J. M. Jeon, "A Study on the ENIG Surface Finish Process and Its Properties", J. Kor. Inst. Surf. Eng., 40(1), 32 (2007). https://doi.org/10.5695/JKISE.2007.40.1.032
  13. JESD22-B117A (Solder Ball Shear), JEDEC Standard, Jul. (2006).
  14. A. -M. Yu, C. -W. Lee, M. -S. Kim and J. -H. Lee, "The Effect of the Addition of In on the Reaction and Mechanical Properties of Sn-1.0Ag-0.5Cu Solder Alloy", Met. Mater. Int., 13(6) 517 (2007). https://doi.org/10.1007/BF03027912
  15. J. Sopousek, M. Palcut, E. Hodulova and J. Janovec, "Thermal Analysis of the Sn-Ag-Cu-In Solder Alloy", J. Electron. Mater., 39(3), 312 (2010). https://doi.org/10.1007/s11664-009-1070-2
  16. C. S. Yoo, S. S. Ha, B. K. Kim, J. K. Jang, W. C. Seo and S. B. Jung, "Interfacial Reaction and Mechanical Property of BGA Solder Joints with LTCC Substrate", J. Kor. Inst. Met. & Mater., 47(3), 202 (2009).
  17. J. H. Ahn, K. S. Kim, Y. C. Lee, Y. Kim and S. B. Jung, " Regulation in Shear Test Method for BGA of Flip-chip Packages", J. Microelectron. Packag. Soc., 17(3), 1 (2010).
  18. J. M. Koo, B. Q. Vu, Y. N. Kim, J. B. Lee, J. W. Kim, D. U. Kim, J. H. Moon and S. B. Jung, "Mechanical and Electrical Properties of Cu/Sn-3.5Ag/Cu Ball Grid Array (BGA) Solder Joints after Multiple Reflows", J. Electron. Mater., 37(1), 118 (2007).
  19. J. M. Kim, M. H. Jeong, S. H. Yoo and Y. B. Park., "Effect of Interfacial Microstructures on the Bonding Strength of Sn- 3.0Ag-0.5Cu Pb-free Solder Bump", Jpn. J. Appl. Phys., 51(5), 05EE06 (2011).
  20. H. Nishikawa, K. Miki and T. Takemoto, "Effect of Aging Conditions on Impact Strength of Sn-3.5Ag Based Soder Joint", Proc. 9th Electronics Packaging Technology Conference (EPTC), Singapore, 553, IEEE Components, Packaging and Manufacturing Technology Society (CPMT) (2007).

Cited by

  1. Effect of Aging treatment and Epoxy on Bonding Strength of Sn-58Bi solder and OSP-finished PCB vol.21, pp.4, 2014, https://doi.org/10.6117/kmeps.2014.21.4.097