Light‐Controlled Mechanical Self‐Assembly for Programmable Surface Micro–Nano Patterning

Abstract Mechanical self‐assembly is a novel manufacturing principle for programmable surface micro‐nano patterning, which can be accurately triggered by interface stress mismatch‐induced surface instability and regulated by high‐precision boundary constraints. However, existing mechanical self‐assembly fabrication strategies for micro‐nano surface patterns face challenges in microfabrication compatibility and industrial repeatability. Here, a microfabrication‐compatible light‐controlled mechanical self‐assembly is proposed for programmable and industrially standardized micro‐nano surface patterning. By introducing light‐controlled high spatial resolution soft‐constraint boundaries and surface instability‐induced mechanical self‐assembly into film/substrate systems, a develop‐free and industrially standardized manufacturing process with microfabrication compatibility is demonstrated. Moreover, trans‐scale patterns spanning from 5 to 1000µm, 2D highly‐ordered patterns, and dynamic patterns mimicking Chinese pandas eating bamboo are achieved. Design criteria for programmablely fabricating trans‐scale patterns and the mechanical mechanism of orderliness evolutions in 2D self‐assembly under arbitrary exposure angles are explained. Furthermore, by applying the highly‐ordered micro‐nano patterns, a new self‐adaptive wideband gas detection system based on tunable micro‐gratings is developed and methane is detected. This study can advance strategies for programmable surface micro‐nano patterns and lay the foundation for the applications of surface functional devices.