Mirror-symmetry controlled mechanical response of interconnects for stretchable electronics

Abstract

With the advent of stretchable electronics, the numerous applications including wearable devices, optoelectronics, and implantable medical devices are realized and thus interconnects that can stretch/deform help to attain these stretchable electronic devices have gained extensive attention. Here, we present a novel spiral interconnect design that utilizes the mirror-topology wherein spiral connect to island in symmetry about the centerline, in contrast to the conventional no-mirror configuration. We fabricate the microscale stretchable mirror configurations for triangular networks and experimentally demonstrate their stretching profiles. A systematic comparison using experiments and FEM modeling illustrates enhanced mechanical response of mirror network by lowering von Mises stress up to ∼20%. The mirror configuration also achieves the higher stretchability. Additionally, interconnects of mirror triangular network experience the identical deformations and stress, as compared to dissimilar stress states in the no-mirror counterpart. We further validate the presented scheme to the complex stretchable arrays i.e. hexagonal arrays. Our experimental and FEM results corroborate with each other. Our proposed configuration can help to customize the deformations and its corresponding stretching profiles, which in turn provide the predictive response of the stretchable networks.