Ultra-Thin, Ultra-Conformal Neural Interfaces

We report a conformal ultra-thin brain electrode array which can nicely wrap around and attach firmly to folds of the brain aiming for a complete neural mapping. We employ a water-soluble silk film serving as the supporting layer to make the ultrathin device (with a total thickness of 2.2 microns) easier to manipulate during device assembly and installation. The ultra-thin device can attach the folds of the curved brain and conformally wrap over the curved cortex after the dissolution of the silk protein film without generating hazardous byproducts. Compared with existing cortical brain electrodes, our electrode arrays are advantageous in terms of the conformal mapping area/sites and the signal quality. Our approach provides opportunities for a complete neural mapping of the whole brain cortex including both the gyri and sulci.