Research of electrophysical properties of composite dielectric material with low permittivity

The active development of telecommunication systems operating at frequencies from 30 GHz and above (including 5G systems) requires the development and creation of materials with a dielectric constant of less than 2.2 compatible with printed circuit board technology. Technological approaches to manufacturing such materials are based on the formation of air cavities in the initial dielectric matrix and require control of their microwave parameters (primarily the dielectric constant and the tangent of the dielectric loss angle) in a given frequency range. The paper presents the results of a study of the electrophysical properties of a composite dielectric material with a low dielectric constant. Sealed dielectric plates with a predetermined volume distribution of air cavities were produced using mechanical perforation and additive 3D printing technology. The microwave parameters of the obtained samples were determined using a detachable cylindrical resonator at a frequency of ~10 GHz. Samples with a minimum dielectric constant of 1.75 were examined. It has been established that the use of additive 3D printing technologies, due to several features, leads to a distortion of the geometric dimensions of the forming air cavities, which in turn affects the electrophysical properties of the samples. The results obtained can be used in the development of new microwave materials.