Dielectric Metasurface from Solution‐Phase Epitaxy of ZnO Nanorods for Subtractive Color Filter Application

Abstract In recent years, metasurfaces have received considerable attention owing to their versatile range of applications. However, in the case of metal‐oxide‐based dielectric metasurfaces, the difficulty and cost of a conventional top‐down nano‐fabrication process largely hinder their applications. In this work, a fabrication method is proposed for dielectric metasurfaces based on the solution‐phase epitaxy of ZnO nanorods. Using this method, precise control of the size and position of the synthesized ZnO nanostructures is achieved. Furthermore, a functional subtractive color filter is also designed and fabricated using this approach. The diameters of the synthesized ZnO nanorods range from 180 to 320 nm, and the subtractive color filter exhibits a wide color tuning ability from yellow to magenta to cyan. Such solution‐based bottom‐up fabrication of ZnO nanorods eliminates the need for dry etching, and demonstrates the potential to grow high‐aspect‐ratio ZnO nanostructures for efficient dielectric metasurfaces.