Advanced manufacturing of dielectric meta-devices

Abstract

Metasurfaces, composed of two-dimensional nanostructures, exhibit remarkable capabilities in shaping wavefronts, encompassing phase, amplitude, and polarization. This unique proficiency heralds a transformative paradigm shift in the domain of next-generation optics and photonics, culminating in the development of flat and ultrathin optical devices. Particularly noteworthy is the all-dielectric-based metasurface, leveraging materials such as titanium dioxide, silicon, gallium arsenide, and silicon nitride, which finds extensive application in the design and implementation of high-performance optical devices, owing to its notable advantages, including a high refractive index, low ohmic loss, and cost-effectiveness. Furthermore, the remarkable growth in nanofabrication technologies allows for the exploration of new methods in metasurface fabrication, especially through wafer-scale nanofabrication technologies, thereby facilitating the realization of commercial applications for metasurfaces. This review provides a comprehensive overview of the latest advancements in state-of-the-art fabrication technologies in dielectric metasurface areas. These technologies, including standard nanolithography [e.g., electron beam lithography (EBL) and focused ion beam (FIB) lithography], advanced nanolithography (e.g., grayscale and scanning probe lithography), and large-scale nanolithography [e.g., nanoimprint and deep ultraviolet (DUV) lithography], are utilized to fabricate highresolution, high-aspect-ratio, flexible, multilayer, slanted, and wafer-scale all-dielectric metasurfaces with intricate nanostructures. Ultimately, we conclude with a perspective on current cutting-edge nanofabrication technologies.