There has been much interest recently in materials that have softness close to the brain tissue for chronic biocompatible interface with the brain.
Much evidence has shown that in both surface and penetrating settings, softer and more compliant materials (e.g. silicone) could minimize the micromotion induced injury and inflammatory response. However to date, the maximum number of electrodes on compliant arrays are still below 30, with also rather limited electrode performance. In this thesis talk, I will present a unique pathway towards large scale, high-density stretchable neural interfaces. Instead of trying to reinvent new stretchable electrode/interconnect materials for ultra-soft arrays, we have been leveraging existing performance-proven polymers, metals and low-impedance coatings, but rendering them stretchable by nanomeshing. These functional multilayer nanomesh structures are attractive due to their nanoscale textures are much smaller than microscale interconnect and electrode patterns, enabling properties almost as ‘intrinsic’, fully compatible with conventional microelectronic layout and fabrication processes. A key milestone of this research is a 256 channel stretchable microelectrode arrays with single-neuron sized electrodes while with less than 200kΩ impedance. Together, this research provides a realistic pathway towards ultra compliant neural interfaces with high performance and large throughput.
- Professor Hui Fang (Advisor)
- Professor Sarah Ostadabbas
- Professor Yongmin Liu