Electric current induced liquid metal flow: Application to coating of micropatterned structures

Although electric fields have been widely used to induce flow of electrolytes, electrically induced long-range flow of metallic liquids has never been reported. Here we show that liquid pure metals can be made to flow in a continuous stream by applying an electric current to an underlying conductive film. This flow occurs in the direction of applied current and is thought to be driven by liquid electromigration. The phenomenon is expected to engender many applications where controlled delivery of a continuous liquid metal stream is desired, such as microfluidics, nanolithography, and patterned conformal coatings. The last application is demonstrated here.