A multiaxial stretchable interconnect using liquid-alloy-filled elastomeric microchannels

We report on the fabrication and characterizations of a multiaxial stretchable interconnect using room-temperature liquid-alloy-filled elastomeric microchannels. Polydimethylsiloxane (PDMS) microchannels coated at the bottom with a gold wetting layer were used as the reservoirs which were subsequently filled by room-temperature liquid alloy using microfluidic injection technique. Using a diamond-shaped geometry to provide biaxial performance, a maximum stretchability of 100% was achieved (ΔR=0.24Ω). Less than 0.02Ω resistance variation was measured for 180° bending. Active electronics, light emitting diode, was also integrated onto the PDMS substrate with stretchable interconnects to demonstrate stable electrical connection during stretching, bending, and twisting.