Integration of 2D and 3D Thin Film Glassy Carbon Electrode Arrays for Electrochemical Dopamine Sensing in Flexible Neuroelectronic Implants

• Published in: Advanced functional materials Vol. 25; no. 1; pp. 78 - 84
• Main Authors: VanDersarl, Jules J., Mercanzini, André, Renaud, Philippe
• Format: Journal Article
• Language: English
• Published: Blackwell Publishing Ltd 07.01.2015
• Subjects: Arrays; biomedical implants; Carbon; Carriers; Devices; dopamine; electrochemistry; Electrodes; flexible implants; Glassy carbon; Surgical implants; Thin films; Titanium
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.201402934

Here we present the development and characterization of a flexible implantable neural probe with glassy carbon electrode arrays. The use of carbon electrodes allows for these devices to be used as chemical sensors, in addition to their typical use as electrical sensors and stimulators. The devices are fabricated out of polyimide, platinum, titanium, and carbon with standard microfabrication techniques on carrier wafers. The devices are released from the substrate through either chemical or electrochemical dissolution of the underlying substrate material. The glassy carbon electrode arrays are produced through the pyrolysis of SU‐8 pillars at 900 °C as the first process step, as this temperature is incompatible with the other device materials. The process demonstrated here is generally applicable, allowing for the integration of various high temperature materials into flexible devices. Incorporating glassy carbon electrodes into flexible neural probes allows for implants to be used as chemical sensors as well as electrical sensors and stimulators. The devices are microfabricated on carrier wafers out of polyimide, platinum, titanium, and glassy carbon. The process demonstrated here is generally applicable for the integration of various high temperature materials into flexible devices.