Strip dielectric wave guide antenna-for the measurement of dielectric constant of low-loss materials

1993 ◽  
Vol 14 (7) ◽  
pp. 1471-1483
Author(s):  
Alok Kumar Rastogi ◽  
A. K. Tiwari ◽  
R. P. Shrivastava
1963 ◽  
Vol 41 (8) ◽  
pp. 1314-1320 ◽  
Author(s):  
I. R. Dagg ◽  
G. E. Reesor

A method of measurement of the real and imaginary parts of the dielectric constant of low-loss liquids is described. The real part of the dielectric constant is derived from the impedance change at an air–dielectric interface in a wave guide; the imaginary part is derived from attenuation measurements made on a liquid-filled guide. The results of initial measurements on carbon tetrachloride and heptane in the frequency range 8.2 to 12.4 Gc/s are given.


2018 ◽  
Vol 2018 (1) ◽  
pp. 000476-000482 ◽  
Author(s):  
Masao Tomikawa ◽  
Hitoshi Araki ◽  
Yohei Kiuchi ◽  
Akira Shimada

Abstract Progress of 5G telecommunication and mm radar for autopilot, high frequency operation is required. Insulator materials having low loss at high frequency is desired for the applications. We designed the low dielectric constant, and low dielectric loss materials examined molecular structure of the polyimide and found that permittivity 2.6 at 20GHz, dielectric loss 0.002. Furthermore, in consideration of mechanical properties such as the toughness and adhesion to copper from a point of practical use. Dielectric properties largely turned worse when giving photosensitivity. To overcome the poor dielectric properties, we designed the photosensitive system. After all, we successfully obtained 3.5 of dielectric constant and 0.004 of dielectric loss, and 100% of elongation at break. In addition, we offered a B stage sheet as well as varnish. These materials are applicable to re-distribution layer of FO-WLP, Interposer and other RF applications for microelectronics.


Author(s):  
Dragos C. Geambasu ◽  
Tuta Leontin ◽  
Marian G. Banciu ◽  
Liviu Nedelcu ◽  
Ioan Nicolaescu

Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 574
Author(s):  
Zhicai Zhu ◽  
Liqin Yao ◽  
Qilong Zhang ◽  
Hui Yang

In this paper, homogeneous polystyrene (PS) microspheres with controllable sizes of 40 nm, 80 nm, and 120 nm were synthesized by controlling the temperature of solvothermal method. In order to explore the effect of PS microspheres on dielectric-hydrophobic properties of the composite films, the composite films containing polystyrene, Polydimethylsiloxane, and P(VDF-TrFE) with high dielectric and hydrophobicity were successfully prepared by a simple and feasible solution blending method. The dielectric constant and hydrophobicity of composite films were boosted by increasing the mass fraction of PS content and decreasing the size of PS due to the enhanced interfacial polarization and the uniform surface micro bulge structure. Meanwhile, the composite films maintain a low loss tangent. Typically, the dielectric constant with 5 wt.% 40 nm PS reached to 29 at 100Hz, which is 4 times that of PDMS/P(VDF-TrFE) (mass ratio: 2/3). Otherwise, the largest the contact angle of 126° in the same composition was remarkably larger than the pure PDMS/P(VDF-TrFE) (110°). These improved properties have more potential applications in the electric wetting devices.


1993 ◽  
Vol 115 (2) ◽  
pp. 219-224 ◽  
Author(s):  
R. K. Agarwal ◽  
A. Dasgupta

A mechanistic model is presented for predicting the effective dielectric constant and loss tangent of woven-fabric reinforced composites with low-loss constituents. A two-scale asymptotic homogenization scheme is used to predict the orthotropic effective properties. A three-dimensional unit-cell enclosing the characteristic periodic repeat pattern in the fabric weave is isolated and modeled mathematically. Electrostatic boundary value problems (BVP’s) are formulated in the unit-cell and are solved analytically to predict effective dielectric constant of the composite, using three-dimensional series-parallel reactance nets. Results are also verified numerically, using finite element methods. The effective dielectric constant and the effective loss tangent are then obtained, analogous to mechanical viscoelastic problems for low-loss materials. The predicted dielectric constant and loss tangent are compared with experimental results for E-glass/epoxy laminates. Frequency dependence of the effective dielectric constant and loss tangent is obtained from the corresponding behavior of the constituent materials. Trade-off studies are conducted to investigate the effect of the constituent material properties on orthotropic effective dielectric permittivity.


Sign in / Sign up

Export Citation Format

Share Document