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The paper presents generalization of micromechanical control principle for number of microwave devices, such as tunable phase shifters and resonator based filters. Starting with one dimensional dielectric discontinuity model, control principle is propagated to microstrip line devices and dielectric resonators. Maximum possible tuning range is discussed along with accompanying insertion loss.
This paper presents the experience in designing LTCC antennas operated in F-band (90–140 GHz). A few examined structures are presented and their electrical parameters dependencies on LTCC technology limitations are shown. The paper is focused on two main aspects: the first one is related to the quality of multi-layered structures and the second one to the properties of metallization, which has a big...
Thin wave absorbers composed of a periodic structure of metal patches have been investigated in order to reduce the radar cross section (RCS). To achieve stable operation for absorbing frequency at oblique incident angles, a high value of permittivity of the substrate or a very thin substrate are required. This paper presents the RCS reduction characteristics of a metasurface absorber with 0.1-mm...
In this paper, an analytical solution shows that an ultrathin anisotropic ε-near-zero (AENZ) metamaterial (MM) layer backed by a metallic substrate can perfectly absorb an incident plane wave at a critical angle. The perfect absorption angle can be controlled by changing the loss of the AENZ MMs. An ultrathin microwave absorber is designed using meander-line MMs with a thickness of only λ/29. By changing...
Electromagnetic energy loss in the micro-mechanically tunable microstrip line is studied including dielectric loss in substrate's medium and ohmic loss in metal electrodes. When total loss in the device is relatively small, loss mechanisms contribute additively, so complex effective permittivity can be used to account both phenomena. This simplifies analysis and design of tunable microstrip lines...
A metal mesh shows Drude-like metallic effective permittivity dispersion. By cutting all wires of the mesh, the metal mesh becomes a metal cross array and shows Lorentz-like effective permittivity dispersion. We prepared the samples of metal mesh with random cut systematically and measured the transmission spectra in the terahertz region. The spectra show a characteristic change from metallic to insulating...
We proposed a simple scheme to make a continuous metallic film on a semi-infinite substrate optically transparent, thus obtaining a completely transparent electrode in a desired frequency range. By placing a sub-wavelength composite layer consisting of dielectric and metallic stripes on top of the metallic one, we found that the back-scattering from the metallic film can be almost perfectly canceled...
We report on a bistable light transmission through two-layered structure which consists of two gratings of planar perfectly conducting infinite strips placed on the both sides of a dielectric slab. It is demonstrated that a switching may be achieved nearly the frequency of the high-quality-factor Fano-shape trapped-mode resonance excitation.
The nonlinear interaction of two Fano-shape resonances in the bilayered structure made of two gratings of planar perfectly conducting infinite strips placed on both sides of the Kerr-type nonlinear dielectric slab is analyzed. The first resonance is obtained due to the trapped-mode excitation in each grating of curvilinear strips. The second one is a result of the interaction of the antiphased current...
We report on a bistable light transmission through a planar metamaterial consisted of a metal pattern of weakly asymmetric elements placed on a nonlinear substrate which enables sharp resonance response by excitation of a trapped mode. A feedback required for bistability is provided by the coupling between strong trapped mode resonance antiphased currents exited on the metal elements and an intensity...
Reflection of a plane electromagnetic wave from the fine-stratified structure located on a metal substrate is considered. A number of features caused by specific properties of effective permittivity are arises. It has been shown, that dependences on a frequency and magnetic field allow to change polarizing characteristics (field ellipticity).
Based on a Z-shaped metal structure, two new types of left-handed materials (LHMs): LHM with units of off-plane anti-symmetric Z-shapes (OPAZ) and LHM with units of in-plane orthogonal Z-shapes (IPOZ) are proposed. In the OPAZ LHMs, the double-negative left-handed band is proved to be in the range from 9.35 GHz to 10.67 GHz by extracting effective permittivity and permeability from the simulated scattering...
We provide an overview of recently published research on the effect of planar substrate dielectric anisotropy and metal surface roughness. The effect of metal roughness on loss is shown to be substantially different from that predicted by commonly used models. Roughness has also been shown to have a substantial effect on velocity of propagation/effective dielectric constant due to the introduction...
In this paper, a novel approach has been suggested to get spurious free window of dielectric resonator (DR) in MIC environment. In MIC environment, due to smaller thickness of substrate with respect to cavity dimension, the position of DR becomes asymmetric within the cavity. Due to this asymmetry, the field configuration of resonance mode modifies from its symmetry value and mode separation gets...
The dispersion relation for propagation and attenuation constants of electromagnetic waves which are supported by a metal film placed on a substrate and covered by a thin dielectric layer is studied numerically in visible and infrared wavelength ranges.
The problem of visible and IR light diffraction by planar 2-D periodic metal-dielectric structures with a periodic cell consisted of two complex-shaped asymmetric metal elements was solved. The mapped PSTD method and ADE technique with complex-conjugate pole model were used for taking into account the dispersion of metal permittivity. The conditions of light confinement by an excitation of trapped...
Theory of the propagation of transverse surface waves in piezoelectric ceramic/metal coupled media is developed. Dispersion equations relating phase velocity to material constants for the existence of various modes are obtained in simple mathematic form for a piezoelectric material of class 6 mm. Piezoelectricity allows a nonleaky but dispersive wave of one or two modes to exist under conditions when...
A new guiding structure which consists of high permittivity tapes inserted in the horizontal mid-plane of a below cutoff parallel metal waveguide was proposed for the realization of mass productive and low loss dielectric waveguides. In this paper, a supporting technique of the high permittivity tape was considered. A guiding structure consisting of the high permittivity tapes attached on a low permittivity...
Coplanar waveguide transmission lines and vertical interconnects are implemented on a thick (15 mum) Parylene-N dielectric layer over a lossy CMOS-grade Si substrate. Devices are measured up to 40 GHz and show very low loss behavior. Low loss tangent and low dielectric constant characteristics of Parylene-N result in significant improvement of transmission lines and interconnects compared to those...
We have prepared metal/insulator/metal (MIM) structures with RuO2 bottom electrode and TiO2 dielectric film for advanced dynamic random access memory (DRAM) technology. RuO2 films were grown by metal organic chemical vapour deposition while TiO2 films were prepared by atomic layer deposition. RuO2 bottom electrode crystallizes in rutile structure and induces growth of rutile TiO2. Equivalent oxide...
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