{1381} revision 2 modified: 02-17-2017 00:05 gmt

A novel pattern transfer technique for mounting glassy carbon microelectrodes on polymeric flexible substrates

  • Use inert-atmosphere pyrolysis @ 900 - 1000 C of 20um SU-8 (which is aromatic) on a thermal oxide wafer.
  • Followed by spin & cure of PI.
  • Demonstrate strong carbonyl bonding of the glassy carbon with mechanical and FTIR testing.
  • Use of photosensitive PI allows through-vias to connect Cr/Au conductive traces.

PMID-28084398 Highly Stable Glassy Carbon Interfaces for Long-Term Neural Stimulation and Low-Noise Recording of Brain Activity

  • Use EIS to show superior charge-injection properties + stability of glassy carbon electrodes vs. Pt electrodes.
    • GC lasted > 5e6 pulses; Pt electrodes delaminated after 1e6 pulses.
    • Hydrogen bonding (above) clearly superior than neat PI-Pt interface
  • GC electrodes were, true to their name, glassy and much smoother than the platinum electrodes.
  • Further reduced impedance with PEDOT-PSS coating.
    • PEDOT-PSS coating on glassy carbon was, in their hands, far more stable than PEDOT-PSS on platinum.
  • All devices, GC, PEDOT:PSS, and Pt, had similar biocompatibility in their assay (figure 7)