A microassembly structure for intracortical three-dimensional electrode arrays

A practical microassembly process has been developed to create three-dimensional (3D) microelectrode arrays for recording and stimulation in the central nervous system using micromachined 2D probe components. Orthogonal lead transfers between the probes and a cortical surface platform are formed by attaching gold beams on the probes to pads on the platform using wire-free ultrasonic bonding. The low-profile (150 μm) outrigger design of the probes allows the bonding of fully-assembled high-density arrays. Micromachined microtools allow full array assembly in about 30 minutes. Arrays having up to 8×16-shanks on 200 μm centers have been realized and used to record cortical single units successfully. Dynamic insertion devices have also been explored to allow the implantation of these high-density probe arrays into feline cortex at high speed