Development and characterization of a fully flexible stimulation system based on embedded liquid metal channels

Neuronal stimulation systems design is highly impacted by the overall resolution and adaptability of the device to the targeted application and area to stimulate. In this study is proposed a novel design for neural micro-stimulation electrode presenting high resolution and adaptability to any targeted area via a high flexibility. The use of liquid metal micro-channels encapsulated into a polymer allowed micro-stimulation pads at the tip of the channels. It presented a high degree of patternability to match different possible applications, as well as flexibility and interesting mechanic properties to make it insertable and adaptable in soft tissues. The design, fabrication process, and study of the electrical and mechanical behavior and stability of the device are discussed. Conductive U-shaped micro-channels down to a total diameter of 110 μm could be produced.