Lithography-free TiO₂/HfO₂/Cr/Ge/Mo multilayer for high-temperature infrared camouflage and heat dissipation

Abstract

To enhance the heat-dissipation capacity of infra-red (IR) stealth structures in high-temperature environments, a selective heat emitter with multi-band thermal management is fabricated. This emitter comprises a high-temperature-resistant titanium dioxide (TiO₂)/hafnium dioxide (HfO₂)/Cr/Ge/Mo multi-film-layer structure. Additionally, the thickness of each layer is determined by the transfer-matrix algorithm. The emissivity of the structure across the IR band is simulated, and its electric field distributions are analyzed across different wavelengths. The stealth-and heat-dissipation bands of the structure are calculated to confirm its overall stealth and heat-dissipation capabilities. The results reveal that the average emissivities of the fabricated TiO₂/HfO₂/Cr/Ge/Mo multi-film-layer structure decrease to 0.21 and 0.27 within 3-5 and 8-14 µm atmospheric window bands, respectively, achieving the IR concealment effect. Conversely, the average emissivities of the structure increase to 0.56 and 0.80 within the 2.5-3 and 5-8 μm non-atmospheric window (NAW) bands, respectively. These high-emissivity bands enhance radiative heat dissipation to reduce heat accumulation and further weaken the detection and characterization of thermal signals. The simulated thermal images confirm the IR-stealth effect of the structure within a wide temperature range. Moreover, its efficient NAW heat-dissipation capability improves its operating life in high-temperature environments.

Keywords

infrared camouflage / selective emitter / radiative heat dissipation / thermal management

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Funding

National Natural Science Foundation of China(52106099)

Science and Technology Development Joint Fund of Henan province(225200810077)