A novel assembly method for 3-dimensional microelectrode array with micro-drive

This paper reports a novel assembly method for 3-dimensional (3D) microelectrode array with the aid of anisotropic conductive film (ACF). For this purpose, a unique silicon probe with trenches encircled bonding pads was fabricated to realize the ACF-bonding with flexible cable. This design is meaningful because it can realize planar bonding for subsequently convenient 3D stacking and the time-consuming plating is not needed to form bumping on pads. The reliability of the ACF-bonding is demonstrated by measuring the electrochemical impedance spectra (EIS) of the bonded probes with different structural and dimensional bonding pads. The bonded probes are further assembled into 3D arrays and integrated with micro-drive for chronic neural recordings. The excellent recording performance indicates that the ACF-bonded probes are reliable and suitable for chronic neural recordings.