Benzocyclobutene (BCB) based intracortical neural implant

Photosensitive benzocyclobutene (photo-BCB) is a class of photoimagable polymers developed for microelectronics under the trade name Cyclotene™ with properties that we believe make it an attractive candidate for chronic implant applications. We report for the first time a complete microfabrication process of BCB polymer-based intracortical neural implant for chronic application. The new design of the implant provides flexibility for micromotion compliance at the brain/implant interface and the necessary stiffness for better surgical handling. We have demonstrated that the implant with a silicon backbone layer of 5∼10 μm is robust enough to penetrate the pia without buckling, a major drawback with polymer. The averaged impedance value at 1 KHz was ∼250 KΩ.