Biomedical Microdevices

, Volume 13, Issue 3, pp 441–451

Novel multi-sided, microelectrode arrays for implantable neural applications


    • Department of Electrical EngineeringUniversity of Michigan
  • Nick B. Langhals
    • Department of Electrical EngineeringUniversity of Michigan
  • David J. Anderson
    • Department of Electrical EngineeringUniversity of Michigan
  • Daryl R. Kipke
    • Department of Electrical EngineeringUniversity of Michigan

DOI: 10.1007/s10544-011-9512-z

Cite this article as:
Seymour, J.P., Langhals, N.B., Anderson, D.J. et al. Biomed Microdevices (2011) 13: 441. doi:10.1007/s10544-011-9512-z


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 recordingMicroelectrode arrayParyleneNeural prosthesesDrug deliveryChemical mechanical polishing

Supplementary material

10544_2011_9512_MOESM1_ESM.jpg (423 kb)
Supplemental Fig. 1Electric 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)

Copyright information

© Springer Science+Business Media, LLC 2011