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Characteristics of Plated Bump on Multi-layer Build up PCB by Pulse-reverse Electroplating

Pulse-reverse도금을 이용한 다층 PCB 빌드업 기판용 범프 생성특성

  • Seo, Min-Hye (Plant Engineering Center, Institute for Advanced Engineering) ;
  • Kong, Man-Sik (Plant Engineering Center, Institute for Advanced Engineering) ;
  • Hong, Hyun-Seon (Plant Engineering Center, Institute for Advanced Engineering) ;
  • Sun, Jee-Wan (Research and Development Team, Hojinplatech) ;
  • Kong, Ki-Oh (Research and Development Team, Hojinplatech) ;
  • Kang, Kae-Myung (Department of Materials Engineering, Seoul National University of Technology)
  • Published : 2009.03.27

Abstract

Micro-scale copper bumps for build-up PCB were electroplated using a pulse-reverse method. The effects of the current density, pulse-reverse ratio and brightener concentration of the electroplating process were investigated and optimized for suitable performance. The electroplated micro-bumps were characterized using various analytical tools, including an optical microscope, a scanning electron microscope and an atomic force microscope. Surface analysis results showed that the electroplating uniformity was viable in a current density range of 1.4-3.0 A/$dm^2$ at a pulse-reverse ratio of 1. To investigate the brightener concentration on the electroplating properties, the current density value was fixed at 3.0 A/$dm^2$ as a dense microstructure was achieved at this current density. The brightener concentration was varied from 0.05 to 0.3 ml/L to study the effect of the concentration. The optimum concentration for micro-bump electroplating was found to be 0.05 ml/L based on the examination of the electroplating properties of the bump shape, roughness and grain size.

Keywords

References

  1. Y. Tsukada, J. Jpn. Inst. Electron. Pack., 11(5), 306 (1996)
  2. D. Schattka, S. Winkels and J. W. Schultze, Metalloberflache, 51, 823 (1997)
  3. J. Winkler, Jr. US patent 1,951,893 (1934)
  4. G. Perger and P.M. Robinsom, Met. Finish, 77 (1979)
  5. D. Landolt and A. Marlot. Surf. Coat. Technol., 8, 169 (2003)
  6. A. Amdi, Acid copper plating of prined circuits, p. 38, Product Finishing, OHIO, USA (1981)
  7. M. H. Seo, H. S. Hong and W. S. Jung, Kor. J. Mater. Res., 18(3), 117 (2008) https://doi.org/10.3740/MRSK.2008.18.3.117
  8. J. C. Puippe and F. Leaman, Theory and Practice of Pulse Plating, p. 43, Amer. Electro Platers Soc., Orlando Florida, USA, (1986)
  9. M. Schlesinger and M. Paunovic, Modern Electroplating, 4th ed., p. 15, M. Schlesinger and M. Paunovic, John Wiley & Sons, New York, USA, (2000)
  10. S. Venkatesan, A. V. Gelatos and V. Misra, Tech. Dig. Int. Conf. Electron Devices Meeting(IEEE, Piscattaway, 1997) p.769
  11. J. J. Kelly and A. C. West, J. Electrochem. Soc., 145 (1998)