The hybrid material is based on both liquid metal and solid metal alloys. The team first created a film using silicone-based substrate called polydimethylsiloxane (PDMS). They then formed a metallic bi-layer by evaporating gallium onto a sputtered gold film a mere 60 nanometers thick. When the solid part of the gold alloy is stretched, cracks can form, but they're quickly filled by the liquid gallium, which has a melting point of 29.8 degrees Celcius (85.6 degrees F). Best of all, the final material can be lithographed onto any surface in complex patterns just like regular electronic circuits.

Without the need to print circuits on a board, the team has dreamed up all kinds of usage scenarios. "We can integrate conventional electronics into assemblies that stretch and carry power, we can use it in soft robotics and smart clothing... but we can also use it to construct actuators that give tactile feedback," says graduate student Arthur Hirsch. In other words, electronics can finally work with our squishy human bodies or help researchers create more life-like robots with liquid metal circuits. Hm, wait a second ...