Advancements in atomic-scale interface engineering for flexible electronics: Enhancing flexibility and durability

Abstract Flexible electronics, such as wearable displays, implantable electronics, soft robots, and smart skin, have garnered increasing attention. Despite notable advancements in research, a bottleneck remains at the product level due to the prevalent use of polymer-based materials, requiring encapsulation films for lifespan extension and reliable performance. Multilayer composites, incorporating thin inorganic layers to maintain low permeability towards moisture, oxygen, ions, etc, exhibit potential in achieving highly flexible barriers but encounter challenges stemming from interface instability between layers. This perspective offers a succinct review of strategies and provides atomic-scale interface modulation strategy utilizing atomic layer integration technology focused on enhancing the flexibility of high-barrier films. It delves into bendable multilayers with atomic-scale interface modulation strategies, encompassing internal stress and applied stress modulation, as well as stretchable composite structural designs such as gradient/hybrid, wavy, and island. These strategies showcase significant improvements in flexibility from bendable to stretchable while maintaining high barrier properties. Besides, optimized manufacturing methods, materials, and complex structure design based on atomic-scale interface engineering are provided, better aligning with the future development of flexible electronics. By laying the groundwork for these atomic-scale strategies, this perspective contributes to the evolution of flexible electronics, enhancing their flexibility, durability, and functionality.