Reliability study of stretchable electronics interconnect by simulation

In this paper, the stretchable interconnect is taken as the research object and its reliability has been analyzed by simulations. Polydimethylsiloxanes (PDMS), as a hyper elastic material, is used here as the stretchable interconnect substrate because of their high elastic property and high stretchability. Traditionally, metals are still the best options to realize the interconnections due to good electronic conductivity and mechanical elongation [1]. Based on that, gold, copper and silver are taken in the simulations for evaluating their performance. Different with other researchers to take curved routing profile shape, “dog bone” shape has been used in this paper due to considering the electro-magnetic confliction and lower requirements of stretchability in our practical application [2]. In order to optimize the designs and metal foil layout, different layout patterns have been considered as the optimized parameters, through the simulations with load condition of elongation and bending, the equivalent principal strain and Mises stress are taken from the different simulation cases to have comparison. Based on that, the reliability of different designs has been evaluated. The pattern of metal foil in plane has been evaluated, as well as the substrate thickness, different materials etc. Without loss of generality, with or without the two rigid components are involved in the model are taken to evaluate the metal foil reliability under the different load condition. The metal foil can be fabricated with different width and thickness, and as well as different methods, all these cases had also been simulated. By all these simulations, all the stretchable interconnect designs and combinations had been evaluated. The design suggestions have been made according to the simulation results analysis.