Biomedical Microdevices

, Volume 13, Issue 3, pp 441–451 | Cite as

Novel multi-sided, microelectrode arrays for implantable neural applications

  • John P. SeymourEmail author
  • Nick B. Langhals
  • David J. Anderson
  • Daryl R. Kipke


A new parylene-based microfabrication process is presented for neural recording and drug delivery applications. We introduce a large design space for electrode placement and structural flexibility with a six mask process. By using chemical mechanical polishing, electrode sites may be created top-side, back-side, or on the edge of the device having three exposed sides. Added surface area was achieved on the exposed edge through electroplating. Poly(3,4-ethylenedioxythiophene) (PEDOT) modified edge electrodes having an 85-μm2 footprint resulted in an impedance of 200 kΩ at 1 kHz. Edge electrodes were able to successfully record single unit activity in acute animal studies. A finite element model of planar and edge electrodes relative to neuron position reveals that edge electrodes should be beneficial for increasing the volume of tissue being sampled in recording applications.


Neural recording Microelectrode array Parylene Neural prostheses Drug delivery Chemical mechanical polishing 



We are grateful to Prof. Joerg Lahann and Dr. Yaseen Elkasabi for providing the reactive parylene dimer and for conducting the CVD polymerization in their laboratory. Ning Gulari provided the critical idea of using CMP in this process and other helpful conversations. Drs. Pilar Herrera-Fierro, Hung-Chin Guthrie, and Ramin Emami shared their considerable CMP expertise which was vitally important. Dr. Kip Ludwig shared his method and software for automatic neural spike sorting. Dr. Mohammad Abidian and Eugene Daneshvar engaged in many helpful discussions regarding conductive polymers. We gratefully acknowledge support from the NIH P41 Center for Neural Communication Technology (EB002030) through the NIBIB.

Supplementary material

10544_2011_9512_MOESM1_ESM.jpg (423 kb)
Supplemental Fig. 1 Electric potential slices and geometries from a three-dimensional COMSOL 4.0a model for each combination of neuron position and electrode type. Electric potential (V) shown in xy-plane cutting through the electrode. (a) Planar electrode. (b) Thin edge electrode, 0.5 μm thick. (c) Thick edge electrode, 5.0 μm thick. (JPEG 423 kb)


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • John P. Seymour
    • 1
    Email author
  • Nick B. Langhals
    • 1
  • David J. Anderson
    • 1
  • Daryl R. Kipke
    • 1
  1. 1.Department of Electrical EngineeringUniversity of MichiganAnn ArborUSA

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