Metal-Free Antennas by Laser-Induced Graphene (LIG) on Poly-Ether-Ether-Ketone (PEEK) Films for Application to Cyber Prostheses

The current trend of personalized medicine fosters additive manufacturing techniques to fabricate custom polymeric prosthetic devices. Inevitably, metal replacement requires the use of deposition techniques to integrate electronic circuits into the device, which poses challenges in terms of adhesion. The laser induction of Graphene (LIG) is a novel solution for scribing conductor-less circuits onto polymeric precursors. In this paper, we hence present the first experimental demonstration of a LIG-based implanted antenna for establishing a through-the-body telemetry link. To achieve a reliable communication performance the sheet resistance of the trace was minimized down to 4 Ω/sq, by finding the optimal laser parameters. Then, a first prototype of a metal-free implanted LIG tapered dipole was fabricated and tested. The antenna, deep-seated in a muscle phantom at 35 mm implantation depth, demonstrated a safe 15 dB power margin with just 5 dB loss with respect to copper.