Plasmonic color filters fabricated via oxide-based nanotransfer printing

Plasmonic filters have recently become a topic of significant interest because they are suitable for a wide range of applications. However, effective fabrication of plasmonic filters remains a challenge. In this paper, we demonstrate a simple method for fabricating plasmonic color filters based on nanotransfer printing (nTP) , using SiO₂ as a hard mask for Al etching. nTP was performed on a 100 nm Al layer deposited on a glass wafer substrate with a 10 nm Al layer and a 20 nm SiO₂ layer with a nanohole pattern. The 10 nm Al layer and 20 nm SiO₂ layers were previously transferred from a polymer stamp prepared to create patterns of subwavelength-sized holes. The plasmonic filters were ultimately fabricated using the SiO₂ layer as a hard mask to selectively etch the Al layer. The optical properties of the fabricated plasmonic filters were evaluated using experimental and simulation tools. In addition, we analyzed the results of nTP on the Al and SiO₂ films by varying the temperature, pressure, and SiO₂-film thickness. We believe that this technique is a promising method for fabricating nanostructures and for widening the scope of practical application of plasmonics because of its high efficiency and cost-effectiveness.