Review for Micro-Nano Processing Technology of Microstructures and Metadevices

As a popular artificial composite material emerging in recent years, metasurfaces are one of the most likely devices to break through the volume limitation of conventional optical components due to their compact structure, flexible materials, and high modulation resolution of the beam. With a unique arrangement of units or made of special materials, the metasurface can effectively modulate the incident light's amplitude, phase, polarization, and frequency, thus realizing applications such as communication, imaging, sensing, and beam steering. The interaction of high-resolution structure, periodic arrangement, and unique constituent materials makes it possible to realize these applications, so researchers should choose the appropriate micro-nano processing technologies when designing and preparing the metasurface. This review will present micro-nano processing technologies related to the preparation of metasurfaces, such as electron beam lithography (EBL), femtosecond laser processing, focused ion beam lithography (FIB), additive manufacturing, nanoimprinting, and self-assembly, respectively. In addition, classical lithography techniques such as wet lithography, plasma lithography, deep reactive ion etching (DRIE), and photolithography will be introduced. Their development history and functions are described in detail, and examples of these techniques in preparing micro-nano-structures in different branches are presented, as well as some examples of metasurface preparation using these techniques. In addition, this paper has produced several tables describing these technologies, outlining their resolution, processing materials, advantages and disadvantages, and so on. Hopefully, this review will provide researchers with options and ideas for preparing metasurfaces.