Hostname: page-component-586b7cd67f-2brh9 Total loading time: 0 Render date: 2024-11-29T07:26:53.579Z Has data issue: false hasContentIssue false
  • English
  • Français

Fabrication and Characterization of Platinum-Iridium Electrodes with Micro-Structured Surfaces For Neural Stimulation Applications

Published online by Cambridge University Press:  15 March 2011

Sachin S. Thanawala ,
Daniel G. Georgiev ,
Afzal Khan ,
Ronald J. Baird  and
Gregory Auner
Sachin S. Thanawala
Affiliation:
Department of Biomedical Engineering, Wayne State University, Detroit, MI-48202
Daniel G. Georgiev
Affiliation:
Department of Electrical and Computer Engineering, Wayne State University, Detroit, MI-48202
Afzal Khan
Affiliation:
Department of Electrical and Computer Engineering, Wayne State University, Detroit, MI-48202
Ronald J. Baird
Affiliation:
Department of Electrical and Computer Engineering, Wayne State University, Detroit, MI-48202
Gregory Auner
Affiliation:
Department of Electrical and Computer Engineering, Wayne State University, Detroit, MI-48202
Get access

Abstract

Controlled structuring of electrode surfaces on a microscopic scale is expected to decrease the impedance and improve the current injection capabilities of neural stimulation electrodes. We have identified conditions for the fabrication of micro-bumps on platinum-iridium alloy surfaces by means of KrF excimer laser (λ=248nm) irradiation under ambient conditions. A regular array of closely spaced micro-bumps with diameters of about 5µm and heights of about 3µm was generated on the polished face of a platinum-20%iridium wire with a diameter of 75µm. A projection system with a demagnification factor of 9 was used to image a mask with a pattern of circular-holes on the polished face of the wire. Several thousand pulses at a repetition rate of 10Hz and a fluence of 3.0 J/cm2 were applied to produce the micro-bumps. The modified electrode surfaces were studied by optical microscopy and scanning electron microscopy, and the results show the formation of micro-bumps of reproducible shape. Simple two-electrode AC impedance measurements in physiological saline in the frequency range of interest to neural stimulation applications show a considerable decrease in the impedance of micro-structured electrodes with respect to the impedance of a polished electrode.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 820: Symposia O/R – Nanoengineered Assemblies and Advanced Micro/Nanosystems , 2004 , O8.11
Copyright
Copyright © Materials Research Society 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Humayun, M. S., Juan, E., Weiland, J. D., Dagnelie, G., Katona, S., Greenberg, R., and Suzuki, S., Vision Research 33, 2569 (1999).Google Scholar
2. Hesse, L., Schanze, T., Wilms, M., and Eger, M., Graefe's Arch. Clin. Exp. Ophthalmol. 238, 840 (2000).Google Scholar
3. Robblee, L. S. and Rose, T. L., “Electrochemical Guidelines for Selection of Protocols and Electrode Materials for Neural Stimulation,” Neural Prosthesis Fundamental Studies, ed. Agnew, W. F. and McCreery, D. B. (Prentice Hall, 1990) pp.26–66.Google Scholar
4. Eckmiller, R., Ophthalmic Research. 29, 281 (1997).Google Scholar
5. Wyatt, J. and Rizzo, J., IEEE Spectrum, 33, 47 (1996).Google Scholar
6. Boer, R.W. de and Oosterom, A. van, Med. and Biol. Eng. and Comput. 16, 1 (1978)Google Scholar