Electrical Performance of Fractal Web as Flexible Interconnects

Spiderweb is one of the most mechanically robust and optimized naturally available structure, which can withstand multidirectional forces, in addition to the fact that the structure works even if one or more spiral lines are broken. Such a design can be worked with as an important model to develop conformal, lightweight, and stretchable electronic configuration like arrays of sensors environment for healthcare applications. Interconnects in flexible electronic circuit play a significant role on its performance and multiple types of geometries have its inspiration from biological world. In this work, fractal spiderweb based interconnect design is studied for mechanical strength and compared with similar dimensional other available intercommons using finite element method (FEM). A third order fractal web architecture is designed with gold layer integrated over polyimide. Prominent flexible interconnect geometries and their electrical performance is compared with that of fractal web architecture. The design is studied under axial load in two perpendicular directions and under shear load in six radial directions. Electrical parameters i.e., resistance and maximum electric field intensity of the simulated structure under loading conditions were observed when the fractal nodes are cut radially and spirally.

I. Introduction

Flexible electronics is an emerging area in the field of consumer to healthcare to energy applications and is entering in almost every field of engineering slowly, because of the attractive advantages such as lightweight, bendable, adaptive into unique shapes [1] . The flexible devices need to be conformal in nature so that the deployment of the devices is possible for diverse applications with being customized. The stretchable circuits shall be efficient with excellent mechanical bendability properties as well as electrical characteristics [2] . Conventional flexible circuit consists of active or passive components, power sources, and high-density interconnects connecting the components for small, medium, and large distances embedded on an elastomeric substrate. The materials for designing and developing flexible electrodes and interconnects vary from metallic nanowires, liquid metals, carbon nanomaterials, conducting polymers to conductive composites [2] .