Stretchable and Transparent Wiring for Implant Sensor

Abstract

A implantable neural interface that can record and control neural activities has been researched and developed as a sensor for the purpose of diagnosis, treatment, and elucidation of serious neurological diseases such as Parkinson's disease, epilepsy, etc. Recently, we have developed a neural interface using a stretchable transparent wiring comprised with Au-plated Ag nanowires. The neural interface realized long-term implantation in the rat's brain, and simultaneous optogenetic stimulation and electrocorticogram recording on the marmoset's cerebral cortex. In this paper, we describe overview of the wiring technologies using the Ag nanowires toward realization of high transparency, conductivity, stretchability, and electrochemical durability. Moreover, a miniaturization technology of Ag nanowire based transparent wiring is described in the aim of not only to improve the spatial resolution of the implantable sensor but also to integrate it in flexible electronics such as display, touch panel, solar cell, wearable sensor, etc. In the future, our developed wiring technologies under solution process will enable to realize a stretchable and transparent electronics with fabrication area from fine scale (several tens to several hundreds of μm) to large scale (several tens cm).