Opto-μECoG array: Transparent μECoG electrode array and integrated LEDs for optogenetics

In this work, we developed an integrated Opto-μECoG array, which allows multi-channel, bi-directional interaction with neurons. The Opto-μECoG array comprises a 6×5 distribution of epidural microelectrodes (~200 μm diameter) for electrical recording and embedded light emitting diodes (LEDs) for optical neural stimulation. Transparent electrodes were fabricated with indium tin oxide (ITO). Commercially available LED chips were self-assembled on a flexible polymer substrate as light sources. Parylene C served as the main structural and packaging material for flexibility and biocompatibility. Electrical and optical characteristics of the fabricated device were studied and in-vivo experiments were performed to investigate the efficacy of the device.