A Simple Bandwidth Broadening Method of Terahertz Metamaterial Absorber by Partially Removing The Dielectric Layer

A five-band metamaterial absorber (MMA) is presented. The proposed absorber consists of a three-layer structure of the top metal resonator, intermediate dielectric layer, and bottom metal plane. The top structure takes the centroid as the center and spreads out in a three-pronged shape with an average of 360°, and the ends bifurcate again. The calculation was carried out by the professional software to iteratively optimize the absorption effect of MMA in the microwave range. The results show that the MA has five peaks at resonant frequencies of 5.984 GHz, 12.232 GHz, 18.128 GHz, 18.414 GHz, and 20.592 GHz, with peaks of 0.9925, 0.9968, 0.9783, 0.9754, and 0.9975. By analyzing the electromagnetic field and surface current distribution of the absorber, the absorption mechanism is further verified, and the corresponding influence on the absorption spectrum is studied according to different polarization angles and incident angles. The effects of different resonator structure size and dielectric layer thickness on absorption rate were also discussed, and the distribution of electromagnetic fields is analyzed to reveal the existence of electric dipole resonance and magnetic resonance. Through comparing experiments and simulations, it is found that the peaks of the 1st, 2nd, and 5th have smaller absorption errors and frequency deviation, while the peaks of the 3rd and 4th have large ones. The five-band absorber has potential application in multiband electromagnetic stealth, bionic sensor, thermal radiation measuring instrument, and so on.

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Toward an Ultra-Wideband Hybrid Metamaterial Based Microwave Absorber

Micromachines ◽

10.3390/mi11100930 ◽

2020 ◽

Vol 11 (10) ◽

pp. 930

Author(s):

Aicha El Assal ◽

Hanadi Breiss ◽

Ratiba Benzerga ◽

Ala Sharaiha ◽

Akil Jrad ◽

...

Keyword(s):

Dielectric Layer ◽

Ground Plane ◽

Transverse Magnetic ◽

Metamaterial Absorber ◽

Microwave Absorber ◽

Ultra Wideband ◽

Periodic Pattern ◽

Frequency Range ◽

Coupled Resonators ◽

Weight Percentage

In this paper, we propose a novel design of an ultra-wideband hybrid microwave absorber operating in the frequency range between 2 GHz and 18 GHz. This proposed hybrid absorber is composed of two different layers that integrate a multiband metamaterial absorber and a lossy dielectric layer. The metamaterial absorber consists of a periodic pattern that is composed of an arrangement of different scales of coupled resonators and a metallic ground plane, and the dielectric layer is made of epoxy foam composite loaded with low weight percentage (0.075 wt.%) of 12 mm length carbon fibers. The numerical results show a largely expanded absorption bandwidth that ranges from 2.6 GHz to 18 GHz with incident angles between 0° and 45° and for both transverse electric and transverse magnetic waves. The measurements confirm that absorption of this hybrid based metamaterial absorber exceeds 90% within the above-mentioned frequency range and it may reach an absorption rate of 99% for certain frequency ranges. The proposed idea offers a further step in developing new electromagnetic absorbers, which will impact a broad range of applications.

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Influence of size on absorption characteristics of a metamaterial absorber with a grating structure in the visible and infrared regimes

Canadian Journal of Physics ◽

10.1139/cjp-2013-0242 ◽

2013 ◽

Vol 91 (12) ◽

pp. 1086-1089 ◽

Cited By ~ 1

Author(s):

Yan-Lin Liao ◽

Yan Zhao

Keyword(s):

Computer Simulation ◽

Layer Thickness ◽

Dielectric Layer ◽

Coupling Effect ◽

Blue Shift ◽

Metamaterial Absorber ◽

Resonance Absorption ◽

Wide Angle ◽

Metallic Grating ◽

Absorption Characteristics

The influence of size on absorption characteristics of a metamaterial absorber with a metallic grating as the top layer is investigated with computer simulation. The resonance absorption peak will redshift by increasing the width of the grating strip, and by adding either the dielectric layer thickness or the grating strip height, the resonance absorption will shift toward shorter wavelengths. The coupling effect between grating strips leads to a blue shift as the gap increases. Such characteristics may be useful to design a reflective wide-angle wavelength-selected device.

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Frequency Controllable Metamaterial Absorber by an Added Dielectric Layer

10.1063/1.3573764 ◽

2011 ◽

Author(s):

Xiong Li ◽

Qin Feng ◽

Xiangang Luo ◽

Minghui Hong

Keyword(s):

Dielectric Layer ◽

Metamaterial Absorber

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Single-peak-regulation and wide-angle dual-band metamaterial absorber based on hollow-cross and solid-cross resonators

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020200145 ◽

2020 ◽

Vol 91 (3) ◽

pp. 30901

Author(s):

Yibo Tang ◽

Longhui He ◽

Jianming Xu ◽

Hailang He ◽

Yuhan Li ◽

...

Keyword(s):

Transverse Electric ◽

Surface Current ◽

Dielectric Substrate ◽

Transverse Magnetic ◽

Metamaterial Absorber ◽

Absorption Peak ◽

Dual Band ◽

Single Peak ◽

Wide Angle ◽

Surface Current Density

A dual-band microwave metamaterial absorber with single-peak regulation and wide-angle absorption has been proposed and illustrated. The designed metamaterial absorber is consisted of hollow-cross resonators, solid-cross resonators, dielectric substrate and metallic background plane. Strong absorption peak coefficients of 99.92% and 99.55% are achieved at 8.42 and 11.31 GHz, respectively, which is basically consistent with the experimental results. Surface current density and changing material properties are employed to illustrate the absorptive mechanism. More importantly, the proposed dual-band metamaterial absorber has the adjustable property of single absorption peak and could operate well at wide incidence angles for both transverse electric (TE) and transverse magnetic (TM) waves. Research results could provide and enrich instructive guidances for realizing a single-peak-regulation and wide-angle dual-band metamaterial absorber.

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Assessment of Reliability of cap layers used in Cu-Black DiamondTM Interconnects

MRS Proceedings ◽

10.1557/proc-766-e2.9 ◽

2003 ◽

Vol 766 ◽

Author(s):

Ahila Krishnamoorthy ◽

N.Y. Huang ◽

Shu-Yunn Chong

Keyword(s):

Dielectric Layer ◽

Dielectric Breakdown ◽

Copper Ions ◽

Dielectric Strength ◽

Time Dependent ◽

Breakdown Field ◽

Field Range ◽

Time Dependent Dielectric Breakdown ◽

Voltage Ramp ◽

Low K

AbstractBlack DiamondTM. (BD) is one of the primary candidates for use in copper-low k integration. Although BD is SiO2 based, it is vastly different from oxide in terms of dielectric strength and reliability. One of the main reliability concerns is the drift of copper ions under electric field to the surrounding dielectric layer and this is evaluated by voltage ramp (V-ramp) and time dependent dielectric breakdown (TDDB). Metal 1 and Metal 2 intralevel comb structures with different metal widths and spaces were chosen for dielectric breakdown studies. Breakdown field of individual test structures were obtained from V-ramp tests in the temperature range of 30 to 150°C. TDDB was performed in the field range 0.5 – 2 MV/cm. From the leakage between combs at the same level (either metal 1 or metal 2) Cu drift through SiC/BD or SiN/BD interface was characterized. It was found that Cu/barrier and barrier/low k interfaces functioned as easy paths for copper drift thereby shorting the lines. Cu/SiC was found to provide a better interface than Cu/SiN.

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