Simulation and fabrication of electromagnetic shielding metallic mesh microstructure based on germanium substrate

The design and production of metallic mesh based on germanium substrate were investigated to satisfy the electromagnetic shielding requirements of germanium optical windows. Through theoretical analysis of the effect of metallic mesh structure on optical transmittance and electromagnetic shielding effectiveness, CST software is used to simulate the effect of metallic mesh period, thickness and substrate resistivity on electromagnetic shielding. According to the simulation results, appropriate parameters are selected to prepare the mesh microstructure. The mesh structure that meets the requirements was produced using laser direct writing lithography. The metallic mesh microstructure has a 400 μm period and a 12μm line width. The eight to 12μm bands measured by the infrared spectrometer had an 87.1% transmissivity. The lowest electromagnetic shielding efficacy is greater than 28.1dB, while the average electromagnetic shielding efficiency of the 240MHz to 18GHz range is assessed by the vector network analyzer at 34.4 dB. This paper describes the simulation and fabrication of metallic mesh microstructures on germanium substrates. These microstructures have excellent optical and electrical properties, which is very important for the creation of optical windows with high optical transmittance and potent electromagnetic shielding.