Complex permittivity of common dielectrics in 20–110 GHz frequency range measured with a Fabry–Pérot open resonator

Abstract

A Fabry–Pérot open resonator is a tool dedicated to broadband accurate microwave and mm-wave characterization of dielectric sheets. It has been applied in this paper to the measurement of the dielectric constant and loss tangent of various types of commonly used dielectric materials, such as semiconductors, electronic substrates, glasses, and plastics, in the 20–110 GHz range. The obtained results are in good agreement with the literature data, which are, however, often available only at discrete frequencies, thus making it difficult to recognize dispersive properties of the measured samples. It is shown in this paper that broadband measurement of high-resistivity and intrinsic silicon allows extracting their resistivity solely due to conduction losses. In the case of typical electronic substrates, it is shown that their dielectric constant is almost non-dispersive, whereas losses are, in general, linearly increasing with frequency. Glasses also exhibit almost non-dispersive dielectric constant, which is, however, larger than 3.8, whereas their losses can vary by over two orders of magnitude depending on the properties, like the hydroxyl content. The lowest dielectric constant is easily achievable in common plastics, spanning from ca. 2.03 for Teflon up to ca. 3.0 for PETG.

Wideband millimeter wave absorber based on coding-metasurface with two-dimensional MXene

“…The 3D printed substrate was 1.27 mm thick and had a measured permittivity of 2.65. It is observed that the measured dielectric permittivity of the substrate deviates from conventional values, 15 , 16 ranging from 2.75 to 2.85, due to the presence of air pockets caused by the 3D printing process, resulting in an effective permittivity. The uniform layer of MXene ink was deposited on the polycarbonate substrate with a measured average thickness of 3.1 μm.…”

Dielectric Characterization of Materials at 5G mm-Wave Frequencies

“…However, there are limited published studies characterizing the GHz dielectric properties of materials suited for 5G applications. While some work has measured insulating materials for printed circuit board (PCB) laminates [7], some materials until 35 GHz in [8], some representative materials from 20 to 110 GHz in [9], and the characterization of silicates until THz frequencies has been done by the authors [10], [11], comprehensive data on ceramics and polymers in the 5G mmWave range is lacking. Bridging this knowledge gap with broadband dielectric metrology is imperative to facilitate the development of 5G-enabled technologies.…”

Tackling Non-linearity in Cavity Perturbation using Machine Learning Approach

“…Moreover, microwave sensors are attractive and growing rapidly for various industrial sensing applications, such as material identification [2]- [3], displacement detection [4]- [5], and biomedical sensing [6]- [7] due to their high measurement accuracy, fast detection ability, low-cost, and noninvasive characteristics. Particularly, resonant methods, in which the material under test (MUT) interacts with a resonant structure, are highly used due to the accuracy and straightforward analysis [8]- [11]. However, as discussed in [8], the resonant cavity technique has a series of limitations mostly arising from nonlinearity.…”