Design and Fabrication of a Flexible Substrate Microelectrode Array for Brain Machine Interfaces

We report a neural microelectrode array design that leverages the recording properties of conventional microwire electrode arrays with the additional features of precise control of the electrode geometries. Using microfabrication techniques, a neural probe array is fabricated that possesses a flexible polyimide-based cable. The performance of the design was tested with electrochemical impedance spectroscopy and in vivo studies. The gold-plated electrode site has an impedance value of 0.9 MΩ at 1 kHz. Acute neural recording provided high neuronal yields, peak-to-peak amplitudes (as high as 100 μV), and signal-to-noise ratios (27dB).