Electrical performance optimization of serpentine interconnect for stretchable electronics

Abstract

Stretchable electronics have a wide range of potential applications in healthcare monitoring and human–machine interactions due to their softness, stretchability, and conformability. Serpentine interconnects integrating with inorganic functional materials play an important role in high-performance stretchable electronics. A lot of research has focused on how to improve the stretchability of flexible electronic devices, while ignoring the intrinsic electrical properties of serpentine wires. In this manuscript, the electrical performance of serpentine interconnects is investigated experimentally. Various structural forms of serpentine interconnects are prepared by photolithography and transfer printing techniques. The electrical properties of serpentine interconnects during stretching are systematically studied and summarized. Besides, a breathable substrate with good biocompatibility and stretchability is used. Based on these studies and the optimization of the design layout, we can guide the selection of wire structures or sensor structures in flexible electronics.

Gallium‐Based Liquid–Solid Biphasic Conductors for Soft Electronics

“…[12,13,22,[14][15][16][17][18][19][20][21] In recent years, multiple conductive materials and fabrication approaches have been proposed for implementation of highly deformable circuits, some of which can withstand large tensile strains without losing electronic functionality. [13,[23][24][25][26] Stretchable functionality in electronic conductors has been accomplished either by engineering mechanically deformable structures (wrinkles, [27][28][29][30][31][32][33] serpentines, [34][35][36][37][38][39][40][41][42] kirigami-inspired structures [43][44][45][46][47][48][49][50][51][52] ) based on rigid metallic conductors (as depicted in Figure 1A-C) or by employing conductive materials that are intrinsically stretchable, for instance, metallic alloys that are liquid at room temperature [53][54]…”

“…Stretchable functionality in electronic conductors has been accomplished either by engineering mechanically deformable structures (wrinkles, [ 27–33 ] serpentines, [ 34–42 ] kirigami‐inspired structures [ 43–52 ] ) based on rigid metallic conductors (as depicted in Figure A–C) or by employing conductive materials that are intrinsically stretchable, for instance, metallic alloys that are liquid at room temperature [ 53–60 ] (Figure 1D) or elastomers filled with conductive particles such as carbon [ 59,61–67 ] or silver [ 61,68–74 ] (Figure 1E,F). This last approach has the advantage of enabling direct printing of soft electronic circuits using low cost and easily scalable methods that contrast with the complex methods of patterning and etching conventional rigid metals.…”