Sustainably Powered, Multifunctional Flexible Feedback Implant by the Bifacial Design and Si Photovoltaics

Advanced design and integration of functioning devices with secured power is of interest for many applications that require complicated, sophisticated, or multifunctional processes in confined environments such as in human bodies. Here, strategies for design and realization are introduced for multifunctional feedback implants with the bifacial design and silicon (Si) photovoltaics in flexible forms. The approaches provide efficient design spaces for flexible Si photovoltaics facing up for sustainable powering and multiple electronic components for feedback functions facing down for sensing, processing, and stimulating in human bodies. The computational and experimental results including in vivo assessments ensure feasibility of the approaches by demonstrating feedback multifunctions, power‐harvesting in milliwatts, and mechanical compatibility for operations in live tissues. This work should useful for wide range of applications that require sustainable power and advanced multifunctions. Sustainably‐powered, bifacial feedback implant enabled by the efficient design strategies of multiple functions and silicon photovoltaics on both sides of the confined substrate in flexible forms. The bifacial implant generates several milliwatt power under skin for feedback functions of standalone sensing, processing, and stimulating while occupying half of the area required for single‐faced one.