A new electromagnetic functional material composed of metallic hollow micro-spheres

摘要

This paper presents a new electromagnetic functional material developed by electron-less nickel deposition technique, with a single hollow micro-sphere as the core template and a thin nickel layer as the shell. The micrograph taken by a scanning electron microscope shows the microstructures of the materials in detail. Scattering parameters of the waveguide sample holder filled with the materials have been obtained over X band. The electromagnetic parameters computed from the measured S parameters show that the material with metallic hollow spheres has as high relative permeability μ'_r as 19.0 with about 0.6 magnetic loss tangent over the whole bandwidth. Compared to the material with non-metallic spheres, the permeability μ'_r and the magnetic loss tangent μ'_r increase greatly, while the permittivity remains lower than 1.8.