The Polymer Society of Korea

Abstract

Metal thin film electrodes are key components in flexible electronics, but their mechanical reliability under bending remains limited. Laminated metal structures composed of multiple thin layers improve strain tolerance, yet further enhancement is required. Here, we report an interlayer engineering strategy to improve the flexibility of laminated metal films. Aluminum was used as the primary conductor, and ultrathin chromium interlayers were inserted between adjacent Al layers. The Cr interlayers reduced the Al grain size and enhanced interfacial adhesion between Al layers, leading to improved mechanical integrity under bending. As a result, Al-Cr laminated films exhibited significantly suppressed resistance increases compared to films without interlayers. These results demonstrate that interlayer engineering is an effective approach for mechanically robust metal electrodes in flexible electronics.