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Embedded copper mesh coatings with low sheet resistance and high transparency were formed using a low-cost Cu seed mesh obtained with a magnetron sputtering on a cracked template, and subsequent operations electroplating and embedding in a photocurable resin layer. The influence of the mesh size on the optoelectric characteristics and the electromagnetic shielding efficiency in a wide frequency range is considered. In optimizing the coating properties, a shielding efficiency of 49.38 dB at a frequency of 1 GHz, with integral optical transparency in the visible range of 84.3%, was obtained. Embedded Cu meshes have been shown to be highly bending stable and have excellent adhesion strength. The combination of properties and economic costs for the formation of coatings indicates their high prospects for practical use in shielding transparent objects, such as windows and computer monitors.

The approaches to creation of the materials providing simultaneously high indicators of transparency in the visible spectrum and shielding in a wide radio frequency band are considered in this paper. The analysis and comparison of the main designs of such materials, as well as approaches to their creation, including multilayer and conductive mesh structures, is carried out. The results of our own theoretical studies of the disordered mesh structure are presented, which allow one to obtain a light transmission coefficient from 90 to 98 % in combination with an electromagnetic interference shielding efficiency from 50 to 65 dB. The best results practically achieved to date (shielding efficiency equal 45 dB in the range from 10 kHz to 20 GHz with a light transparency of more than 80 %) were obtained on mesh structures by photolithography, which is a significant limiting factor of this approach. The created multilayer structures show, in general, lower characteristics. However, the technology for their production is better scaled, and the optimization of the thicknesses and chemical composition of multilayer structures can significantly increase them. In this regard, technological aspects may come to the fore when taking into account the possibility of subsequent scaling of the technology and economic indicators when choosing an approach for the implementation of the materials with the required characteristics.

This paper is a preliminary report on a theoretical study of transparent shielding materials with potentially very high shielding efficiency based on quasi-periodic conductive networks. An empirical model for rapid calculation of shielding efficiency vs frequency and mesh geometrical parameters is suggested based on numerical simulation results.

The study was devoted to the creation of transparent electrodes based on highly conductive mesh structures. The analysis and reasonable choice of technological approaches to the production of such materials with a high Q factor (the ratio of transparency and electrical conductivity) were carried out. The developed manufacturing technology consists of the formation of grooves in a transparent substrate by photolithography methods, followed by reactive ion plasma etching and their metallization by chemical deposition using the silver mirror reaction. Experimental samples of a transparent electrode fabricated using this technology have a sheet resistance of about 0.1 Ω/sq with a light transmittance in the visible wavelength range of more than 60%.