Optimistic design of freestanding horseshoe metal interconnects for stretchable electronic circuits

This work investigates structure analysis and design of metal interconnects for stretchable electronic circuits using the finite element software ABAQUS. In order to design a more promising structure of metal interconnect, the performance of different parameters (the inner radius, the angle and the width of the copper trace) of horseshoe shape is compared under the condition of uniaxial tensile. In the process of finite element simulation, the metal is modeled as elastic-plastic solids. It can be concluded that the most dominating factor for the maximum equivalent plastic strain is the inner radius of horseshoe shape. The maximum plastic strain values decreases as the radius increases. The change tendency of the effect of angles of horseshoe shape is the same as the effect of radius. However, the maximum plastic strain values increase as the widths increase. Building on the results which based on simulated and compared different configurations, an optimistic horseshoe shape with an appropriate inner radius, angle and width is suggested. This design allows a larger deformation with the minimum stress concentration on the top of the arc. However, the stresses and strains is based on substrate stiffness in stretchable electronic. The performance of optimal configurations for the copper line on substrate will need to have a further investigation.