Impact of Black Pad and Intermetallic Layers on the Risk for Fractures in Solder Joints to Electroless Nickel/Immersion Gold

  • P.-E. Tegehall


Solder joints to solder lands plated with electroless nickel and immersion gold are prone to fractures in the interface between the solder and the nickel surface. A common cause for these fractures has been a plating defect in the solder land coating called “black pad”. However, solder joints to solder lands plated with electroless nickel are inclined to fractures even if the black pad defect is not present. The causes of the black pad defect and the mechanisms for the increased inclination for fractures in solder joints to electroless nickel are discussed. Test methods for detecting black pad defects and assessing the risk for fractures in the solder joints are also described.


Solder Joint Phosphorus Content Gold Layer Intermetallic Layer Solder Ball 
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  1. 1.
    Puttlitz KJ (1990) Preparation, structure, and fracture modes of Pb–Sn and Pb–In Terminated flip chips attached to gold-capped microsockets. In: Proceedings of 40th electronic components and technology conference, pp 360–366Google Scholar
  2. 2.
    Eslambolchi A, Johnson P, Kaufmann M, Mei Z (1998) Electroless Ni/immersion Au evaluation—final program report. Electronic Assembly Development Center, Hewlett-Packard, Palo AltoGoogle Scholar
  3. 3.
    Cordes F, Huemoeller R (1999) Electroless nickel–gold: is there a future? Electroless Ni/Au plating capability study of BGA packages. In: proceeding of IPC Printed Circuits Expo, Paper S13-1Google Scholar
  4. 4.
    Kwok RWM, Chan KCM, Bayes MW (2004) Development of an electroless nickel immersion gold process for PCB final finishes. Circuit World 30(3):37–42CrossRefGoogle Scholar
  5. 5.
    Johal K (2001) Are you in control of your electroless nickel/immersion gold process. In: Proceedings of SMTA InternationalGoogle Scholar
  6. 6.
    McFaddin WE (2003) Non-destructive analysis method for detection of the “black pad defect” on PCB surfaces. In: Proceedings of SMTA International, pp 395–403Google Scholar
  7. 7.
    Biunno N (1999) A root cause failure mechanism for solder joint integrity of electroless nickel/immersion gold surface finishes. In: Proceedings of IPC Printed Circuits Expo, Paper S18-5Google Scholar
  8. 8.
    Bulwitch RA, Trosky M, Pichione LM, Hug D (2002) The “black pad” failure mechanism—from beginning to end. Global SMT Packag 2(6):9–13Google Scholar
  9. 9.
    Jay R, Kwong A (2001) Dealing with the “black pad defect”—a failure analyst’s perspective. In: Proceedings of SMTA InternationalGoogle Scholar
  10. 10.
    Champaign RF, Roepsch JA, Downey MR (2003) Afraid of the dark? Circuits Assemb 14(1):22–25Google Scholar
  11. 11.
    Roepsch JA, Champaign RF, Waller BM (2003) Black pad defect: influence of geometry and other factors. In: Proceedings of SMTA InternationalGoogle Scholar
  12. 12.
    Crouse K, Cullen D (2002) A key failure mode resulting in interfacial fracture of soldered ENIG surfaces. PC FAB Mag (Feb):22–32Google Scholar
  13. 13.
    Milad G, Martin J (2000) Electroless nickel/immersion gold, solderability and solder joint reliability as functions of process control. CircuiTree 13(10):56–62Google Scholar
  14. 14.
    Johal K, Lamprecht S, Schreier H-J, Roberts H (2004) Impacts of bulk phosphorous content of electroless nickel layers to solder joint integrity and their use as gold- and aluminum-wire bond surfaces. In: Proceedings of SMTA Pan Pacific Microelectronics SymposiumGoogle Scholar
  15. 15.
    Goosey M (2002) Factors influencing the formation of “black pad” in electroless nickel-immersion gold solderable finishes—a processing perspective. Circuit World 28(3):36–39CrossRefGoogle Scholar
  16. 16.
    Lee B (2003) Implementing a simple corrosion test method to detect “black pad” phenomenon in electroless nickel/immersion gold plating. CircuiTree 16(11):40–46Google Scholar
  17. 17.
    Houghton B (2000) Solving the ENIG black pad problem: an ITRI report on round 2. Future Circuits Int 6:121–128Google Scholar
  18. 18.
    Houghton B (2000) ITRI project on electroless nickel/immersion gold joint cracking. Circuit World 26(2):10–16MathSciNetCrossRefGoogle Scholar
  19. 19.
    Tomia Y, Wu Q, Maeda A, Baba S, Ueda N (2000) Advanced surface plating on the organic FC-BGA package. In: Proceedings of 50th electronic components and technology conference, pp 861–867Google Scholar
  20. 20.
    Bansal A, Yoon S, Mahadev V (2005) Flexural strength of BGA solder joints with ENIG substrate finish using 4-point bend test. In: Proceedings of SMTA Pan Pacific Microelectronic SymposiumGoogle Scholar
  21. 21.
    Design and assembly of process implementation for BGAs (2005) IPC Standard IPC-7095A.
  22. 22.
    Sohn Y-C, Yu Y, Kang SK, Shih D-Y, Lee T-Y (2005) Effect of intermetallics spalling on the mechanical behavior of electroless Ni(P)/Pb-free solder interconnection. In: Proceedings of 55th electronic components and technology conference, pp 83–88Google Scholar
  23. 23.
    Mattila TT, Kivilahti JK (2005) Failure mechanisms of lead-free chip scale package interconnections under fast mechanical loading. J Electron Mater 34(7):969–976CrossRefGoogle Scholar
  24. 24.
    Paik K-W, Jeon Y-D, Cho M-G (2004) Interfacial reactions and bump reliability of various Pb-free solder bumps on electroless Ni-P UBMs. In: Proceedings of 54th electronic components and technology conference, pp 675–682Google Scholar
  25. 25.
    Zheng Y, Hillman C, and McCluskey P (2002) Intermetallic growth on PWBs soldered with Sn3.8Ag0.7Cu. In: Proceedings of 52nd electronic components and technology conference, pp 1226–1231Google Scholar
  26. 26.
    Liu CM, Ho CE, Chen WT, Kao CR (2001) Reflow soldering and isothermal solid-state aging of Sn-Ag eutectic solder on Au/Ni surface finish. J Electron Mater 30(9):1152–1156CrossRefGoogle Scholar
  27. 27.
    Coyle RJ, Hodges Popps DE, Mawer A, Cullen DP, Wenger GM, Solan PP (2003) The effect of modifications to the nickel/gold surface finish on assembly quality and attachment reliability of a plastic ball grid array (Peer Review Version). IEEE Trans Compon Packag Technol 26(4):724–732CrossRefGoogle Scholar
  28. 28.
    Chouta P, Santos D, Srihari H, Sammakia B, Andros F, DiPietro M (2001) A shear strength study of lead-free solder spheres for BGA applications on different pad finishes. In: Proceedings of SMTA Pan Pacific SymposiumGoogle Scholar
  29. 29.
    Sykes B (2005) Lead-free BGA reliability: high-speed bond testing and brittle fracture detection. Global SMT Packag 5(9):20–23Google Scholar
  30. 30.
    Newman K (2005) BGA brittle fracture—alternative solder joint integrity test methods. In: Proceedings of 55th electronic components and technology conference, pp 1194–1201Google Scholar
  31. 31.
    Chiu T-C, Zeng K, Stierman R, Edwards D, Ano K (2004) Effect of thermal aging on board level drop reliability for Pb-free BGA packages. In: Proceedings of 54th electronic components and technology conference, pp 1256–1270Google Scholar
  32. 32.
    Gregorich T, Holmes P, Lee JCB, Lee CC (2004) SnNi and SnNiCu intermetallic compounds found when using SnAgCu solders. In: Proceedings of IPC/Soldertec global 2nd international conference lead free electronGoogle Scholar
  33. 33.
    Wong EH, Rajoo R, Mai YW, Seah SKW, Tsai KT, Yap LM (2005) Drop impact: fundamentals and impact characterisation of solder joints. In: Proceedings of 55th Electronic Components and Technology Conference, pp 1202–1209Google Scholar
  34. 34.
    Hasegawa K, Takahashi A, Noudou T, Nakaso A (2004) Electroless Ni-P/Pd/Au plating for semiconductor package substrates. Plat Surf Finish 91(11):20–25Google Scholar
  35. 35.
    Date M, Shoji T, Fujiyoshi M, Sato K, Tu KN (2004) Impact reliability of solder joints. In: Proceedings of 54th Electronic Components and Technology Conference, pp 668–674Google Scholar
  36. 36.
    JESD22-B111 (2003) Board level drop test method of components for handheld electronic products. JEDEC
  37. 37.
    JESD22-B110A (2004) Subassembly mechanical shock. JEDEC
  38. 38.
    IPC/JEDEC-9702 (2004) Monotonic bend characterization of board-level interconnects. IPC
  39. 39.
    IPC/JEDEC-9704 (2005) Printed wiring board strain gage test guidelines. IPC
  40. 40.
    Ahmad M, Duggan R, Hu T, Ong B, Ralph C, Sethuraman S, Shangguan D (2005) Strain gage testing: standardization. Surf Mt Technol 19(7):36–42Google Scholar

Copyright information

© Springer-Verlag London Limited 2011

Authors and Affiliations

  1. 1.Swerea IVF ABMölndalSweden

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