Infrared low-emission and microwave high-transmission ZnS/Ge multilayer films

In response to the demand for multifunctional materials in complex electromagnetic and thermal radiation environments, a ZnS/Ge periodic multilayer film structure was designed in this study based on photonic crystal bandgap theory and the free-space path loss law by using CST Studio Suite electromagnetic simulation software, by which the tuning of infrared low-emissivity performance was realized. Multilayer film samples were fabricated by using a magnetron sputtering system, and the morphology, infrared, and microwave properties of the films were characterized and measured. The compatible properties of high microwave transmittance and low infrared emissivity were achieved in this study, and key technologies for the design and fabrication of spectrum-compatible materials were broken through. A transmittance of greater than 70% was obtained in the 2.6 GHz~18 GHz band, and an emissivity of no more than 0.2 was obtained in the 3 μm~5 μm and 8 μm~14 μm bands. New insights are considered to be provided by these results for the development of multispectral functional materials in fields such as spacecraft thermal management and satellite communication.