Mechanical Performance Analysis and Optimization of Serpentine Wire Structures in Flexible Electronic Devices

Abstract

Aiming at the fatigue failure of serpentine wire in flexible electronic devices under repeated bending, stretching, and other large deformation scenarios, this paper takes the full-fit serpentine interconnect conductor as the research object, and constructs a three-dimensional model of multilayered heterostructure composed of conductor and substrate based on ABAQUS finite element platform, and systematically researches the influence of the material parameters of the conductor and the substrate on the elongation rate of the serpentine structure, such as elasticity modulus. The material parameters of wire and substrate, including modulus of elasticity, Poisson's ratio, as well as geometric parameters of wire, such as line width, length of the straight-line section, bending radius and their combinations, affect the ductility of the serpentine structure. The experimental results show that the modulus of elasticity of the substrate is positively correlated with the ductility, the increase of the line width of the wire significantly reduces the ductility, the increase of the bending radius effectively improves the ductility, and the influence of the length of the straight-line segment on the ductility is nonlinear; orthogonal tests further reveal the coupling between the geometrical parameters of the wire. The research results provide a theoretical basis for the design of flexure-resistant structures for flexible electronic devices.