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Microsystem Technologies

, Volume 15, Issue 8, pp 1245–1254 | Cite as

Megasonic agitation for enhanced electrodeposition of copper

  • Jens Georg KaufmannEmail author
  • Marc P. Y. Desmulliez
  • Yingtao Tian
  • Dennis Price
  • Mike Hughes
  • Nadia Strusevich
  • Chris Bailey
  • Changqing Liu
  • David Hutt
Technical Paper

Abstract

In this paper we propose an agitation method based on megasonic acoustic streaming to overcome the limitations in plating rate and uniformity of the metal deposits during the electroplating process. Megasonic agitation at a frequency of 1 MHz allows the reduction of the thickness of the Nernst diffusion layer to less than 600 nm. Two applications that demonstrate the benefits of megasonic acoustic streaming are presented: the formation of uniform ultra-fine pitch flip-chip bumps and the metallisation of high aspect ratio microvias. For the latter application, a multi-physics based numerical simulation is implemented to describe the hydrodynamics introduced by the acoustic waves as they travel inside the deep microvias.

Keywords

Trench Print Circuit Board Seed Layer Acoustic Streaming Copper Electrodeposition 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

The authors would like to acknowledge the financial support of the Engineering and Physical Science Research Council (EPSRC) under the grand challenge project entitled “3D-Mintegration” (www.3d-mintegration.com) which is referenced EP/C534212/1. The authors would also like to acknowledge a DTA funding from the UK Engineering and Physical Sciences Research Council (EPSRC) through the Innovative electronic Manufacturing Research Centre (IeMRC).

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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Jens Georg Kaufmann
    • 1
    Email author
  • Marc P. Y. Desmulliez
    • 1
  • Yingtao Tian
    • 2
  • Dennis Price
    • 3
  • Mike Hughes
    • 4
  • Nadia Strusevich
    • 4
  • Chris Bailey
    • 4
  • Changqing Liu
    • 2
  • David Hutt
    • 2
  1. 1.MicroSystems Engineering Centre (MISEC), School of Engineering and Physical ScienceHeriot-Watt UniversityEdinburghUK
  2. 2.Wolfson School of Mechanical and Manufacturing EngineeringLoughborough UniversityLoughboroughUK
  3. 3.Merlin Circuit Technology LTDFlintshireUK
  4. 4.Centre for Numerical Modelling and Process Analysis (CNMPA)University Of GreenwichLondonUK

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