Annals of Biomedical Engineering

, Volume 20, Issue 4, pp 423–437 | Cite as

A glass/silicon composite intracortical electrode array

  • Kelly E. Jones
  • Patrick K. Campbell
  • Richard A. Normann


A new manufacturing technique has been developed for creating silicon-based, penetrating electrode arrays intended for implantation into cerebral cortex. The arrays consist of a 4.2 mm×4.2 mm glass/silicon composite base, from which project 100 silicon needle-type electrodes in a 10×10 array. Each needle is approximately 1,500 μm long, 80μm in diameter at the base, and tapers to a sharp point at the metalized tip. The technique used to manufacture these arrays differs from our previous method in that a glass dielectric, rather than ap-n-p junction, provides electrical isolation between the individual electrodes in the array. The new electrode arrays exhibit superior electrical properties to those described previously. We have measured interelectrode impedances of at least 1013 Ω, and interelectrode capacitances of approximately 50 fF for the new arrays. In this paper, we describe the manufacturing techniques used to create the arrays, focusing on the dielectric isolation technique, and discuss the electrical and mechanical characteristics of these arrays.


Micromachining Electrode array Neural interface Intracortical electrodes 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    Anthony, T.R.; Cline, H.E. Deep-diode arrays. J. Appl. Phys. 47(6):2550–2557; 1976.Google Scholar
  2. 2.
    Campbell, P.K.; Jones, K.E.; Huber, R.J.; Horch, K.W.; Normann, R.A. A silicon-based, three dimensional-neural interface: Manufacturing processes for an intracortical electrode array. IEEE Trans. Biomed. Eng. 38(8):758–768; 1991.CrossRefPubMedGoogle Scholar
  3. 3.
    Jones, K.E.; Campbell, P.K.; Normann, R.A. Interelectrode isolation in a penetrating intracortical electrode array. Proc. Annu. Int. Conf. IEEE Eng. Med. Biol. Soc. 12:496–497; 1990.Google Scholar
  4. 4.
    Leyden, R.N.; Basiulis, D.I. Adhesion and electrical insulation of thin polymeric coating under saline exposure. Mat. Res. Soc. Symp. Proc. 110:627–633; 1989.Google Scholar
  5. 5.
    McHardy, J.; Basiulis, D.I.; Angsten, G.; Higley, L.R.; Leyden, R.N. Accelerated testing of polyimide coatings for neural prostheses. In: Lupinski, J.H.; Moore, R.S., eds. Polymeric materials for electronics packaging and interconnection. ACS Symposium Series 407. 1989: pp. 168–175.Google Scholar
  6. 6.
    Peterson, K.E. Silicon as a mechanical material. Proc. IEEE 70(5):420–457; 1982.Google Scholar
  7. 7.
    Rousche, P.J.; Normann, R.A. A method for pneumatically inserting an array of penetrating electrodes into cortical tissue. Ann. Biomed. Eng. 20:413–422; 1992.PubMedGoogle Scholar

Copyright information

© Pergamon Press Ltd. 1992

Authors and Affiliations

  • Kelly E. Jones
    • 1
  • Patrick K. Campbell
    • 1
  • Richard A. Normann
    • 1
  1. 1.Department of BioengineeringUniversity of UtahSalt Lake City

Personalised recommendations