An Ultra-Conformable Highly Enriched Distributed Brain Electrode

We report an ultra-conformable brain electrode containing 128 recording sites within 0.5×0.25 cm ² area. A through-polymer-via structure and multilayer wiring are used for the highly enriched distribution of recording sites and the nice flexibility of the device. Compared with existing cortical electrodes, this electrode array has a higher density with a thinner thickness (the thinnest overall thickness can reach 4μm), so it can well contact the curved brain surface and collect high-quality brain electrical signals. A water-soluble silk film is served as the supporting layer to make the ultrathin device easier to manipulate and to keep the device conformally wrapping over the curved cortex after being dissolved. The fabricated electrode array proved to be of great mechanical and electrical properties. Based on this device, effective neural recording has been achieved, and differential brain statuses in dynamic processes from seizure to recovery can be efficiently recognized.