Wafer‐Scale 200 mm Metal Oxide Infrared Metasurface with Tailored Differential Emissivity Response in the Atmospheric Windows

Abstract Metasurfaces with sub‐wavelength nanoscale features have emerged as a platform to achieve desirable electromagnetic responses. However, it remains technically challenging to fabricate metasurfaces in large size and at low cost for mass production. This work demonstrates a 200 mm wafer‐scale Al:ZnO metasurface coating based on deep‐UV lithography. The metasurfaces are targeted to achieve infrared (IR) reflectivity and emissivity characteristics at bandwidths across the two atmospheric windows in the IR spectrum. The wafers demonstrate a high uniformity of optical response with tailored reflectivity of around 50% at the 3–5 µm mid‐wave IR band and less than 10% at the 8–13 µm long‐wave IR band. This article furthermore shows that the design principle allows achieving a wide range of dual‐band reflectivity values using a single underlying materials stack, offering a versatile platform. The proposed approach is compatible with CMOS‐compatible mass‐production manufacturing and brings IR metasurface coatings closer to commercially relevant and scalable technology.