Hybrid patterning of metal nanowire/polymer composites based on selective photocuring-and-transfer and kirigami cutting techniques for stretchable circuit application†
Abstract
Despite recent advances in stretchable conductors, developing highly micro-patternable and strain-insensitive electronic circuits remains a challenge. Here, we present a universal microfabrication route for high-performance stretchable devices and circuits composed of silver nanowires (AgNWs) or other functional conductive nanomaterials. An AgNW network film can be precisely patterned into arbitrary shapes using an ultraviolet (UV)-curable polymer (UCP)-mediated selective photocuring-and-transfer (SPT) technique in a simple and reproducible manner, and then, it can be entirely transferred to another UCP sheet while being embedded in it. This facile process allows the preparation of highly robust and flexible AgNW/UCP composite sheets with a low sheet resistance of 0.31 ± 0.05 Ω sq−1 and a minimum patternable size of 50 μm. The AgNW/UCP sheet can be stretched to high strains without considerable degradation of its electrical properties by simply forming kirigami-inspired mechanical cuts. The synergistic hybridization of the SPT micro-patterning and kirigami cutting processes enables us to successfully construct a highly stretchable and easily customizable circuit board for emerging stretchable system applications. As a proof of concept, we successfully implement a light-emitting diode matrix in the AgNW/UCP circuit board; we confirm that the circuit can stably maintain its light-emitting performance even under high strains of 100%.