Ultra‐Deformable and Tissue‐Adhesive Liquid Metal Antennas with High Wireless Powering Efficiency. Issue 26 (25th May 2021)

• Record Type: Journal Article
• Authors: Yamagishi, Kento; Zhou, Wenshen; Ching, Terry; Huang, Shao Ying; Hashimoto, Michinao
• Is Part Of: Advanced materials. Volume 33:Issue 26(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-05-25
• Subjects: antennas -- direct ink writing -- liquid metals -- microchannels -- near‐field‐communication; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202008062
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Flexible and stretchable antennas are important for wireless communication using wearable and implantable devices to address mechanical mismatch at the tissue–device interface. Emerging technologies of liquid‐metal‐based stretchable electronics are promising approaches to improve the flexibility and stretchability of conventional metal‐based antennas. However, existing methods to encapsulate liquid metals require monolithically thick (at least 100 µm) substrates, and the resulting devices are limited in deformability and tissue‐adhesiveness. To overcome this limitation, fabrication of microchannels by direct ink writing on a 7 µm‐thick elastomeric substrate is demonstrated, to obtain liquid metal microfluidic antennas with unprecedented deformability. The fabricated wireless light‐emitting device is powered by a standard near‐field‐communication system (13.56 MHz, 1 W) and retained a consistent operation under deformations including stretching (>200% uniaxial strain), twisting (180° twist), and bending (3.0 mm radius of curvature) while maintaining a high quality factor ( q > 20). Suture‐free conformal adhesion of the polydopamine‐coated device to ex vivo animal tissues under mechanical deformations is also demonstrated. This technology offers a new capability for the design and fabrication of wireless biomedical devices requiring conformable tissue‐device integration toward minimally invasive, imperceptible medical treatments. Abstract : Fabrication of unprecedentedly deformable liquid metal antennas by direct ink writing of silicone microchannels on a 7 µm‐thick elastomeric substrate is demonstrated. Suture‐free conformal adhesion of the polydopamine‐coated thin‐film antenna to ex vivo animal tissues and reliable wireless operations under mechanical deformations are also demonstrated.