Microsystem Technologies

, Volume 15, Issue 5, pp 789–797 | Cite as

Fabrication of compliant high aspect ratio silicon microelectrode arrays using micro-wire electrical discharge machining

  • Dinesh Rakwal
  • Sumet Heamawatanachai
  • Prashant Tathireddy
  • Florian Solzbacher
  • Eberhard Bamberg
Technical Paper


This paper reports on the fabrication of high aspect ratio silicon microelectrode arrays by micro-wire electrical discharge machining (μ-WEDM). Arrays with 144 electrodes on a 400 μm pitch were machined on 6 and 10 mm thick p-type silicon wafers to a length of 5 and 9 mm, respectively. Machining parameters such as voltage and capacitance were varied for different wire types to maximize the machining rate and to obtain uniform electrodes. Finite element analysis was performed to investigate electrode shapes with reduced lateral rigidity. These compliant geometries were machined using μ-WEDM followed by a two step chemical etching process to remove the recast layer and to reduce the cross sections of the electrodes.


Electrical Discharge Machine Work Piece Electrode Array Wire Electrical Discharge Machine Machine Characteristic 
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.



This material is based upon work supported by ProfX2 fellowship grant awarded to Prashant Tathireddy by Fraunhofer Gesellschaft, Germany and equipment developed with support from Optimation, LLC and the National Science Foundation under Grant No. 0512897.


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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Dinesh Rakwal
    • 1
  • Sumet Heamawatanachai
    • 1
  • Prashant Tathireddy
    • 2
  • Florian Solzbacher
    • 2
  • Eberhard Bamberg
    • 1
  1. 1.Precision Design Laboratory, Department of Mechanical EngineeringUniversity of UtahSalt Lake CityUSA
  2. 2.Microsystems Laboratory, Department of Electrical and Computer EngineeringUniversity of UtahSalt Lake CityUSA

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