EMI Shielding Properties of Al, Co, and Al/Co Thin Films

Abstract

In this study, ultra-thin films of Al, Co, and multilayered Al/Co were fabricated using the magnetron sputtering technique on a very thin glass substrate. Subsequently, electromagnetic wave shielding measurements were conducted utilizing the transmission-reflection line method with the aid of a vector network analyzer. In measurements conducted within the X-band microwave frequency range within the waveguide, the maximum electromagnetic interference shielding effectiveness (EMI SE) values obtained were determined as 46 dB for Al, 24 dB for Co, and 48 dB for the multilayered Al/Co film. The structural and morphological analyses of these shielding films were included in the study using x-ray Diffraction (XRD), energy dispersive x-ray analysis (EDAX), Scanning Electron Microscopy (SEM), and Atomic Force Microscopy (AFM) techniques. Scattering parameter results indicated that increasing conductivity values enhance the shielding effectiveness (SE) while also demonstrating an additional positive impact on the SE value for multilayered structures. This finding indicates that nanometer-thick Al or Al/Co multilayer films could significantly protect electronic devices or individuals exposed to X-band microwave radiation. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.