Understanding the Stretching Mechanism of Spiral-Island Configurations for Highly Stretchable Elecronics

Spiral-island is commonly used configuration for highly stretchable and flexible electronics. Here we show the elongations and stress behaviors of spiral-island system. We use the numerical modeling to reveal the stress states along the arms of spirals, especially when the spirals connect in series and as well as triangular configurations between islands. We stretched out the spirals up to 1000 μm and compared the behaviors for single, two and four spirals connected in series. Numerical calculations show that during stretching, the stress is higher near the region of arm’s start i.e. end that is connected to inner circle.. Our result also show that final elongation of spiral and arm’s stresses depend on the angular position and the no. of spirals connected in series. We use the 3D printer to manufacture the spiral-island for triangular configuration and compare the elongation of spirals, which confirm our numerical results.