Fatigue Life Prediction of Serpentine Interconnects on Soft Elastomers for Stretchable Electronics

Serpentine interconnects on soft elastomers have been widely used to develop high-performance stretchable electronics. A number of applications demand the system to sustain repetitive loadings, which lead to fatigue failure of serpentine interconnects. In this paper, the fatigue behavior of serpentine interconnects on an elastomeric substrate is investigated experimentally and theoretically. It is shown that the fatigue failure of serpentine interconnects is governed by the failure of encapsulation layer with the fatigue life determined by the strain level. A fatigue life prediction model, validated by experiments, based on the fatigue modulus concept is established to predict the fatigue life of serpentine interconnects. These results provide physical insights into the fatigue failure of serpentine interconnects and paves the theoretical foundation to predict the fatigue life, thus to study the reliability of stretchable electronics.