Development of Si neural probe with microfluidic channel fabricated using wafer direct bonding

This paper reports the development of a novel Si neural probe with a microfluidic channel to deliver drugs into neural tissue. We fabricated this Si neural probe using wafer direct bonding. To confirm the fluidic capability of the fabricated Si probe, we demonstrated the ejection of liquid from the microfluidic channel using a syringe pump. We confirmed that the Si probe had sufficient bonding strength to eject liquid. In addition, we investigated the pressure drops in the microfluidic channel. From the results, we observed a linear relationship between the flow rate and the pressure drop. Since this result agreed well with the calculated values, we confirmed that the microfluidic channel was successfully formed by wafer direct bonding.