Microstructured Silicone Substrate for Printable and Stretchable Metallic Films

Adam P. Robinson, Ivan Minev, Ingrid M. Graz, and Stephanie P. Lacour.
Nanoscience Centre, Department of Engineering, University of Cambridge (2011).

Stretchable electronics (i.e., hybrid inorganic or organic circuits integrated on elastomeric substrates) rely on elastic wiring. We present a technique for fabricating reversibly stretchable metallic films by printing silver-based ink onto microstructured silicone substrates. The wetting and pinning of the ink on the elastomer surface is adjusted and optimized by varying the geometry of micropillar arrays patterned on the silicone substrate. The resulting films exhibit high electrical conductivity (!11 000 S/cm) and can stretch reversibly to 20% strain over 1000 times without failing electrically. The stretchability of the g200 nm thick metallic !lm relies on engineered strain relief in the printed !lm on patterned PDMS.