Fractal design concepts for stretchable electronics

• Published in: Nature communications Vol. 5; no. 1; p. 3266
• Main Authors: Fan, Jonathan A., Yeo, Woon-Hong, Su, Yewang, Hattori, Yoshiaki, Lee, Woosik, Jung, Sung-Young, Zhang, Yihui, Liu, Zhuangjian, Cheng, Huanyu, Falgout, Leo, Bajema, Mike, Coleman, Todd, Gregoire, Dan, Larsen, Ryan J., Huang, Yonggang, Rogers, John A.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 07.02.2014; Nature Publishing Group
• Subjects: 142/126; 639/301/1005/1007; 639/301/930/1032; Adult; Design, synthesis and processing; Electronic devices; Electronics; ENGINEERING; Epidermis; Fractals; Humanities and Social Sciences; Humans; Male; Mechanics; multidisciplinary; Science; Science (multidisciplinary); Young Adult
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/ncomms4266

Stretchable electronics provide a foundation for applications that exceed the scope of conventional wafer and circuit board technologies due to their unique capacity to integrate with soft materials and curvilinear surfaces. The range of possibilities is predicated on the development of device architectures that simultaneously offer advanced electronic function and compliant mechanics. Here we report that thin films of hard electronic materials patterned in deterministic fractal motifs and bonded to elastomers enable unusual mechanics with important implications in stretchable device design. In particular, we demonstrate the utility of Peano, Greek cross, Vicsek and other fractal constructs to yield space-filling structures of electronic materials, including monocrystalline silicon, for electrophysiological sensors, precision monitors and actuators, and radio frequency antennas. These devices support conformal mounting on the skin and have unique properties such as invisibility under magnetic resonance imaging. The results suggest that fractal-based layouts represent important strategies for hard-soft materials integration. Stretchable electrodes provide the foundation for many applications but optimising the architecture to balance performance and flexibility is challenging. Here, the authors show that fractal designs offer new opportunities to tune the mechanical properties of such structures.