Mass-Production of Visible Metalenses via Wafer-Scale Printing

Currently, metasurface-based flat optics is going from science to technology transition. A representative example includes a flat and ultra-thin metalens, which has potential to overcome the limitations of conventional optical lenses, such as bulky system, heavy weight, shadowing effect, and chromatic aberration. As an example, typical digital single-lens reflex (DSLR) camera which have a length of over 30 cm and a weight of over 4 kg. On the other side, metalens has near-zero weight and nm-scale thickness. However, their inherent fabrication limitations such as high manufacturing cost, low throughput, and small patterning areas hindered their widespread use. In this abstract, we introduce a new fabrication method for the mass production of visible metalenses. The proposed fabrication method includes an argon fluoride immersion scanner, wafer-scale nanoimprint lithography, and atomic layer deposition. The argon fluoride immersion scanner is used to fabricate a 12-inch master stamp. Once a 12-inch master stamp is imprinted, hundreds of 1-centimeter metalenses can be transferred to the substrate. Since nanoimprint lithography features low cost and high throughput, metalenses can be fabricated with extremely low cost and high throughput. However, a low refractive index of printed resin causes low efficiency. To increase the effective refractive index of printed resin, the printed resin is thinly coated with a high-index film. As a result, the conversion efficiency of the designed meta-atom is drastically increased. In this method, we mass-produced 1-centimeter metalenses on a wafer-scale, even in a laboratory environment. As a proof of concept, a VR device integrated with mass-produced metalens was demonstrated. Moreover, the proposed method can also be applied to various metasurfaces such as holograms, color filters, and biosensors.