초록 |
We use multiple patterning colloidal lithography(MPCL) to fabricate a large-scale (2.5 cm × 2.5 cm) near-perfect absorber that is composed of ringshaped TiN structures. To best of our knowledge, it is the first demonstration of applying MPCL to etch a refractory metal, which is focused on the fabrication approach to overcome the limitations of practical use as a large-scale absorber. The device has polarization-independent absorption of 95.4% under normal incidence and high absorption at incident angles up to θ = 40∘ at visible and NIR wavelength (400 < λ < 900 nm). The near-perfect absorption of our device remains even after heating at temperature up to 600 oC. We expect that our cost-effective and scalable absorber is a promising candidate for large-scale applications, such as photothermal devices and thermal emitters that require polarization-independent, angle-insensitive, heat-tolerant, and broadband absorption. |