Hybrid structure of stretchable interconnect for reliable E-skin application

This paper presents the methodology for realisation of stretchable interconnects based on hybrid thin film stack of spray-coated conductive polymer PEDOT: PSS and evaporated gold (Au) film. The PEDOT: PSS film, with its properties in electrical conductivity and mechanical softness, serves as a stress release buffer in the layered hybrid structure. With the serpentine-shape design, the stretchable interconnects can accommodate larger deformation in comparison with a straight line. The correlation between interconnects' morphology (i.e. cracks propagation) with their electrical behaviour has been studied through microscope in along with electrical characterisation under external strain. Furthermore, a comparison in failure strain among different serpentine-shaped designs has been studied. Higher level in stretchability of interconnects can be achieved with a larger arc degree in design. The fabricated stretchable interconnects can accommodate significant deformations up to 72% external strain while maintaining electrically conductive.