Development of three dimensional neural sensing device by stacking method

This study reports a stacking method for assembling a 3-D microprobe array. To date, various 3D array structures have been reported with complex assembly steps, vertical interconnection for 3-D signal transmission which may suffer from low structure strength and large implantable opening. By applying the proposed stacking method, the previous problems were no longer existed. Also, ASIC chips could be substituted for the spacers in the stacked arrays achieving system integration, design flexibility and volume usage efficiency. To avoid overflow of the adhesive fluid during assembly, an anti-overflow design which made use of capillary action force was applied in the stacking method as well. Presented stacking procedure consumes only 35 minutes in average for a 4 × 4 3D microprobe array without requiring specially made assembly tools. The advantages of the proposed stacking method for 3D array assembly include simplified assembly process, high structure strength, smaller opening area and integration ability with active circuits. This stacking assembly technique allows an alternative method to create 3-D structures from planar components.