Wearable electronic devices capable of monitoring the motion of the human physique hold great promise for many functions, including health monitoring, rehabilitation, and gaming, among others. These sensory techniques, also known as artificial or digital skins, provide a seamless and intimate contact with the body allowing the detection of skin elongation and limb movement mapping.
One of the critical challenges in wearable technology is the capability to mix the desired device performance with a satisfactory degree of integration with the body. Presently, the limited elasticity of typical electronic conductors critically limits the creation of electrical circuits able to keep their mechanical and electrical sincerity when interfacing with the body.
In the last decade, some approaches to form stretchable electronic methods have been intended by investigating different material mixtures, fabrication methods, and integration methods. Unfortunately, the adopted fabrication techniques pose constraints in terms of pattern resolution and complexity, film thickness, and device footprint.
Recently, owing to their inherent deformability and high electrical conductivity, liquid metals—i.e., minerals that are liquid at room temperature—have been employed to create stretchable digital conductors. In particular, gallium-based liquid metals have appeared as candidate materials that mix high stretchability with low gauge factor and high electrical conductivity.
In their latest report that appeared in Advanced Intelligent Systems, the research team led by Prof. Stéphanie Lacour (lsbi, EPFL) released a novel wafer-scale manufacturing technique to pattern micrometer-thick-gallium-based mostly films on large-area silicon substrates with high flexibility and fine management over the film microstructure and electromechanical efficiency.