A three-dimensional microassembly structure for micromachined planar microelectrode arrays

We present a new three-dimensional (3-D) microassembly method for planar silicon micromachined electrode arrays, which can be used in implantable neuroprosthetic devices for neural recording and stimulation in the central nervous system (CNS). The new microassembly technique is particularly useful when a modular system architecture is adopted to reduce the number of interconnects between modules (probes). The need for a supporting platform and lead transfer between perpendicular planes has been eliminated by stacking the planar probes with insulating glass or polyimide spacers in between and transferring the leads across the spacer sheets with electroplated gold beams. A 3-D 7×4×4 microelectrode array is fabricated using mock up Interestim-3 probes and 500μm-thick glass spacers.