scholarly journals Structural, Thermal and Dielectric Properties of Low Dielectric Permittivity Cordierite-Mullite-Glass Substrates at Terahertz Frequencies

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4030
Author(s):  
Beata Synkiewicz-Musialska ◽  
Dorota Szwagierczak ◽  
Jan Kulawik ◽  
Norbert Pałka ◽  
Przemysław Piasecki
Keyword(s):  
Dielectric Properties ◽  
Dielectric Permittivity ◽  
Ceramic Composites ◽  
X Ray Diffraction ◽  
Closed Porosity ◽  
Transmission Method ◽  
Glass Substrates ◽  
Low Dielectric ◽  
Effective Dielectric Permittivity ◽  
Terahertz Frequencies

Glass–ceramic composites containing cordierite, mullite, SiO2 glass and SiO2-B2O3-Al2O3-BaO-ZrO2 glass were fabricated in a process comprising solid state synthesis, milling, pressing and sintering. Thermal behavior, microstructure, composition and dielectric properties in the Hz-MHz, GHz and THz ranges were examined using a heating microscope, differential thermal analysis, thermogravimetry, scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction analysis, impedance spectroscopy, transmission method and time domain spectroscopy (TDS). The obtained substrates exhibited a low dielectric permittivity of 4.0–4.8. Spontaneously formed closed porosity dependent on the sintering conditions was considered as a factor that decreased the effective dielectric permittivity.

scholarly journals Sintering, Microstructure, and Dielectric Properties of Copper Borates for High Frequency LTCC Applications

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4017
Author(s):  
Dorota Szwagierczak ◽  
Beata Synkiewicz-Musialska ◽  
Jan Kulawik ◽  
Norbert Pałka
Keyword(s):  
Dielectric Properties ◽  
Dielectric Permittivity ◽  
High Frequency ◽  
Ceramic Materials ◽  
Sintering Behavior ◽  
Terahertz Time Domain Spectroscopy ◽  
Very High Frequency ◽  
X Ray ◽  
Low Dielectric ◽  
Very High

New ceramic materials based on two copper borates, CuB2O4 and Cu3B2O6, were prepared via solid state synthesis and sintering, and characterized as promising candidates for low dielectric permittivity substrates for very high frequency circuits. The sintering behavior, composition, microstructure, and dielectric properties of the ceramics were investigated using a heating microscope, X-ray diffractometry, scanning electron microscopy, energy dispersive spectroscopy, and terahertz time domain spectroscopy. The studies revealed a low dielectric permittivity of 5.1–6.7 and low dielectric loss in the frequency range 0.14–0.7 THz. The copper borate-based materials, owing to a low sintering temperature of 900–960 °C, are suitable for LTCC (low temperature cofired ceramics) applications.

scholarly journals Structural, optical and microwave dielectric properties of Ba(Ti1−xSnx)4O9, 0 ≤ x ≤ 0.7 ceramics

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Asad Ali ◽  
Sarir Uddin ◽  
Madan Lal ◽  
Abid Zaman ◽  
Zafar Iqbal ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Microwave Dielectric Properties ◽  
Orthorhombic Symmetry ◽  
X Ray Diffraction ◽  
Low Dielectric ◽  
Microwave Dielectric ◽  
Ceramic Samples ◽  
Red Color ◽  
High Dielectric ◽  
Quality Factor Q

AbstractSn-doped BaTi4O9 (BT4) dielectric ceramics were prepared by a mixed oxide route. Preliminary X-ray diffraction (XRD) structural study shows that the ceramic samples have orthorhombic symmetry with space group (Pnmm). Scanning electron microscopy (SEM) shows that the grain size of the samples decreases with an increase in Sn4+ content. The presence of the metal oxide efficient group was revealed by Fourier transform infrared (FTIR) spectroscopy. The photoluminescence spectra of the ceramic samples reported red color ~ 603, 604, 606.5 and 605 nm with excitation energy ~ 2.06, 2.05, 2.04 and 2.05 eV for Sn4+ content with x = 0.0, 0.3, 0.5, and 0.7, respectively. The microwave dielectric properties of these ceramic samples were investigated by an impedance analyzer. The excellent microwave dielectric properties i.e. high dielectric constant (εr = 57.29), high-quality factor (Qf = 11,852), or low-dielectric loss (3.007) has been observed.

A versatile foaming platform to fabricate polymer/carbon composites with high dielectric permittivity and ultra-low dielectric loss

2019 ◽  
Vol 7 (1) ◽  
pp. 133-140 ◽  
Author(s):  
Biao Zhao ◽  
Mahdi Hamidinejad ◽  
Chongxiang Zhao ◽  
Ruosong Li ◽  
Sai Wang ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Dielectric Loss ◽  
Dielectric Permittivity ◽  
Carbon Composite ◽  
Carbon Composites ◽  
Low Dielectric ◽  
Composite Foams ◽  
High Dielectric Permittivity ◽  
High Dielectric

A microcellular structure can effectively tune the dielectric properties of PVDF/carbon composite foams.

scholarly journals Effect of TeO2 addition on the dielectric properties of CaCu3Ti4O12 ceramics derived from the oxalate precursor route

2013 ◽  
Vol 03 (04) ◽  
pp. 1350028 ◽  
Author(s):  
P. Thomas ◽  
K. B. R. Varma
Keyword(s):  
Dielectric Properties ◽  
Dielectric Loss ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
Oxalate Precursor ◽  
X Ray ◽  
Practical Applications ◽  
Low Dielectric ◽  
Precursor Route ◽  
Tan Δ

CaCu 3 Ti 4 O 12 (CCTO) ceramics which has perovskite structure gained considerable attention due to its giant permittivity. But it has high tan δ (0.1 at 1 kHz) at room temperature, which needs to be minimized to the level of practical applications. Hence, TeO 2 which is a good glass former has been deliberately added to CCTO nanoceramic (derived from the oxalate precursor route) to explore the possibility of reducing the dielectric loss while maintaining the high permittivity. The structural, morphological and dielectric properties of the pure CCTO and TeO 2 added ceramics were studied using X-ray diffraction, Scanning Electron Microscope along with Energy Dispersive X-ray Analysis (EDX), spectroscopy and Impedance analyzer. For the 2.0 wt.% TeO 2 added ceramics, there is a remarkable difference in the microstructural features as compared to that of pure CCTO ceramics. This sample exhibited permittivity values as high as 7387 at 10 KHz and low dielectric loss value of 0.037 at 10 kHz, which can be exploited for the high frequency capacitors application.

TiO2@Ag/P (VDF-HFP) composite with enhanced dielectric permittivity and rather low dielectric loss

RSC Advances ◽  
2016 ◽  
Vol 6 (73) ◽  
pp. 69580-69585 ◽  
Author(s):  
Xingrong Xiao ◽  
Nuoxin Xu ◽  
Yongchang Jiang ◽  
Qilong Zhang ◽  
Enjie Yu ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
Dielectric Loss ◽  
Dielectric Permittivity ◽  
Hybrid Particles ◽  
Low Dielectric

Ag-loaded TiO2 hybrid particles (TiO2@Ag) were synthesized as fillers and the TiO2@Ag/P(VDF-HFP) composites exhibited enhanced dielectric properties.

Synthesis and Dielectric Behavior of a New Two-Phase Percolative BaTiO3-Cu/Polyimide Composite

2014 ◽  
Vol 670-671 ◽  
pp. 263-266
Author(s):  
Zhi Long Pan ◽  
Jia Ting Chen ◽  
Shi Liang Ao ◽  
Jian Ping Jia
Keyword(s):  
Dielectric Properties ◽  
Dielectric Loss ◽  
Copper Nanoparticles ◽  
Chemical Reduction ◽  
Ferroelectric Material ◽  
Dielectric Behavior ◽  
Two Phase ◽  
Low Dielectric ◽  
Three Phase ◽  
Effective Dielectric Permittivity

The chemical reduction method was used to deposit copper nanoparticles (about 20nm) on the surface of the barium titanate (BT, r=50nm). Then the dielectric properties and the mechanism of BaTiO3-Cu/polyimide composite were studied. The results showed that the effective dielectric permittivity of the composite with 60 wt% of BT-Cu (less than 13.00 wt% of copper) fillers was greater than 120, and the dielectric loss of which was lower than 0.025. Due to very low dielectric loss, so this composite was a two-phase composite material, different from the three-phase composite (metal-ceramics-poly). It was concluded that copper nanoparticles were deposited on the surface of the BT nanoparticles by chemical bond. Owing to good dielectric properties of as-prepared composite, such new two-phase composites had a potential to become the most important ferroelectric material.

ZnTiO3 Doping Effect on Dielectric Properties of CCTO Ceramics via a Molten Salt Process

2012 ◽  
Vol 512-515 ◽  
pp. 1231-1234
Author(s):  
Rong Yu ◽  
Ze Liang Cao ◽  
Hao Xue ◽  
Zhao Xian Xiong
Keyword(s):  
Dielectric Properties ◽  
Nonlinear Coefficient ◽  
Low Frequency ◽  
Composite Ceramic ◽  
Ceramic Composites ◽  
X Ray Diffraction ◽  
X Ray ◽  
Schottky Type ◽  
Ccto Powder ◽  
Molten Salt Process

CaCu3Ti4O12 (CCTO) powder was prepared by solid-state reaction. CCTO-ZnTiO3 composite ceramic were prepared by reaction of CCTO powder with molten ZnCl2 in air, 400°C. The products were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electric and dielectric properties of CCTO-ZnTiO3 composite ceramic were investigated. It is shown that the ceramic composites have higher grain-boundary resistivity and nonlinear coefficient. The addition of Zn mainly formed in the form of ZnTiO3 also affected the low frequency capacitance values, reduced the CCTO ceramic dielectric loss, which showed a Schottky-type nature of potential barrier. Moreover, the mechanisms involved in the NBLC model were discussed, where it is working with the IBLC model.

scholarly journals Investigations on Structural, Mechanical, and Dielectric Properties of PVDF/Ceramic Composites

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Anshuman Srivastava ◽  
Karun Kumar Jana ◽  
Pralay Maiti ◽  
Devendra Kumar ◽  
Om Parkash
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Single Phase ◽  
Extrusion Process ◽  
Ceramic Composites ◽  
X Ray Diffraction ◽  
Composite State ◽  
X Ray ◽  
Embedded Capacitor ◽  
Xrd Patterns

Polymer ceramic composites are widely used for embedded capacitor application. In the present work PVDF has been used as a matrix and CCTO and LaCCTO have been used as reinforcement. Extrusion process has been used for the synthesis of composites. X-ray diffraction (XRD) patterns confirm the formation of single phase CCTO, and LaCCTO in its pure as well as composite state. It is found that La doping in CCTO considerably increases the dielectric constant and reduces the dielectric loss. A similar trend is observed in the composites with the increasing content of CCTO and LaCCTO.

scholarly journals F-TiO2/P(VDF-HFP) hybrid films with enhanced dielectric permittivity and low dielectric loss

RSC Advances ◽  
2017 ◽  
Vol 7 (7) ◽  
pp. 3949-3957 ◽  
Author(s):  
Enjie Yu ◽  
Qilong Zhang ◽  
Nuoxin Xu ◽  
Hui Yang
Keyword(s):  
Dielectric Properties ◽  
Dielectric Loss ◽  
Dielectric Permittivity ◽  
Self Assembly ◽  
Hybrid Films ◽  
Low Dielectric

Self-assembly flower-like TiO2 particles (F-TiO2) were synthesized as fillers and the resulting F-TiO2/P(VDF-HFP) composites exhibited enhanced dielectric properties.

Dielectric Properties and Microstructure of Y-Al-Ga-Si Co-Doped Barium Titanate Ceramics

2014 ◽  
Vol 602-603 ◽  
pp. 700-704
Author(s):  
Min Jia Wang ◽  
Qi Long Zhang ◽  
Xin Hui Zhao ◽  
Hui Yang
Keyword(s):  
Dielectric Properties ◽  
Dielectric Loss ◽  
Barium Titanate ◽  
X Ray Diffraction ◽  
Solid State Method ◽  
Low Dielectric ◽  
Doped Barium Titanate ◽  
Titanate Ceramics ◽  
Functional Components ◽  
Co Doped

Multilayer ceramic capacitors (MLCC) are important functional components of electronic information technology. The development of AC MLCC requires low dielectric loss and high AC breakdown voltage. In this paper, Y-Al-Ga-Si co-doped barium titanate ceramics were prepared by conventional solid state method. Microstructures, surface morphology and dielectric properties were investigated by X-ray diffraction, SEM, and LCR analyzer, respectively. Y3+ entered into the lattice of BaTiO3, replaced A-sites and B-sites, suppressed grain growth effectively, and made crystal structure change from tetragonal to pseudo-cubic, which reduced dielectric loss and lowered the Curie peak. The sintering characteristic and permittivity can be improved by the incorporation of Al and Ga. BaTiO3 -0.06Y2O3 - 0.02Ga2O3 -0.01Al2O3 -0.01SiO2 ceramics sintered at 1380°C achieved good dielectric properties: εr= ~2223, tanδ =~1.1% (at 1kHz), ΔC/C25 <~15.26% (from 55°C to 150°C).

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