Absorption-dominant, low reflection EMI shielding materials with integrated metal mesh/TPU/CIP composite

Recent advances in fifth generation (5G) mobile communication have allowed the development of high data rates, energy efficiency, and system capacity. The demand for millimeter-wave (mmWave) frequency electromagnetic wave shielding materials is also increasing simultaneously. However, current electromagnetic interference (EMI) shielding materials, including metals and composites with dielectric or conductive fillers, typically have a high absorption shielding effectiveness (SEA) with a low reflection shielding effectiveness (SER) at mmWave frequencies. To address this inherent issue of EMI shielding materials, we introduce a metal-mesh-supported polymer composite consisting of a reflection layer and an absorbing layer. The proposed composite shielding material has a SER of only 2 dB and a SEA of 46 dB. The permittivity, permeability, and tangent loss of the absorption layer, as well as the effects of thickness and type of mesh of the mesh-supported polymer composite are discussed. The mechanism of additional absorption capacity due to destructive interference is also discussed in comparison with theoretical calculations. Its shielding efficiency is compared with previously reported values, and a superior absorbance with a thinner thickness of the proposed mesh-supported polymer composite system is observed, which is very proper for 5G EMI shielding applications.