PDMS-Based Neural Microelectrode Arrays for Retinal Prosthesis

Abstract

Abstract: In order to improve the contact between electrode sites and target neurons by using conformable substrates, and meanwhile ensure the reliability of the microelectrode arrays, a new method for fabricating crack-free polydimethylsiloxane (PDMS)-based microelectrode arrays (MEAs) was presented. The device is constructed by depositing, patterning and electroplating gold to form wires and electrode sites on silicon wafer, and then embedding the wires in PDMS, exposing the electrode sites and bonding the second PDMS layer for bottom insulation. The embedding and exposing process involves pouring PDMS on the electroplated metal microstructures, curing with clamping and wet etching PDMS residues. In this way reliable and robust conformable MEAs were achieved. Prototype MEAs were also tested and evaluated by SEM and impedance test. The experimental results show, compared with conventional PDMS-based MEAs, the electrochemical impedance decreases by 60%. The PDMS-based MEAs fabricated by the method proposed in this paper exhibite obvious advantages in mechanical and electrical properties.

Key words: microelectrode array, polydimethylsiloxane(PDMS), electroplated, retinal prosthesis

CLC Number:

TP261

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