Superconducting materials are used in a range of applications including MRI imaging, catheter steering, transport – magnetic levitation trains- and fault current limiters. Superconductivity is the capacity of certain materials to exhibit zero resistance to the passing of an electric current when cooled to low temperatures. Often, a metallic layer is required to create a level of thermal and electrical protection in the case of a fault in the superconducting tape. Sputtered gold and silver-gold alloy layers have proven to have the best combination of properties for this application including electrical and thermal conductivities, contact resistance, specific heat capacities, oxidation potential, lattice constant, and coefficient of linear expansion.
Sputtering is a technology capable of depositing thin films from a wide variety of materials on to diverse substrate shapes and sizes. The process is repeatable and can be scaled up from small research and development projects, to production batches involving medium to large substrate areas.