An impregnation-reduction method to prepare graphite nanosheet/alumina composites and its high-frequency dielectric properties

Rare Metals ◽  
2015 ◽  
Vol 36 (3) ◽  
pp. 205-208 ◽  
Author(s):  
Ke-Lan Yan ◽  
Run-Hua Fan ◽  
Min Chen ◽  
Kai Sun ◽  
Xu-Ai Wang ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
High Frequency ◽  
Reduction Method ◽  
Graphite Nanosheet ◽  
Alumina Composites

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.

LOW-TEMPERATURE ION-PLASMA DEPOSITION TECHNOLOGY OF NANOSTRUCTURED FILMS OF ALUMINUM AND BORON NITRIDES

2021 ◽  
Vol 56 ◽  
pp. 97-107
Author(s):  
M. S. Zayats ◽  
Keyword(s):  
Dielectric Properties ◽  
Low Temperature ◽  
Magnetron Sputtering ◽  
High Frequency ◽  
Plasma Deposition ◽  
Heating Temperature ◽  
Substrate Heating ◽  
Ion Plasma ◽  
Technological Cycle ◽  
Physical And Chemical

A low-temperature (substrate heating temperature up to 400 °C) ion-plasma technology for the formation of nanostructured AlN and BN films by the method of high-frequency reactive magnetron sputtering of the corresponding targets has been developed (the modernized installation "Cathode-1M"), which has in its technological cycle the means of physical and chemical modification, which allow to purposefully control the phase composition, surface morphology, size and texture of nanocrystalline films. The possibility of using the method of high-frequency magnetron sputtering for deposition of transparent hexagonal BN films in the nanoscale state on quartz and silicon substrates is shown. Atomic force microscopy (AFM) has shown that AlN films can have an amorphous or polycrystalline surface with grain sizes of approximately 20-100 nm, with the height of the nanoparticles varying from 3 to 10 nm and the degree of surface roughness from 1 to 10 nm. It was found that the dielectric penetration of polycrystalline AlN films decreases from 10 to 3.5 at increased frequencies from 25 Hz to 1 MHz, and the peak tangent of the dielectric loss angle reaches 0.2 at 10 kHz. Such features indicate the existence of spontaneous polarization of dipoles in the obtained AlN films. Interest in dielectric properties in AlN / Si structures it is also due to the fact that there are point defects, such as nitrogen vacancies and silicon atoms, which diffuse from the silicon substrate during synthesis and play an important role in the dielectric properties of AlN during the formation of dipoles. The technology makes it possible, in a single technological cycle, to produce multilayer structures modified for specific functional tasks with specified characteristics necessary for the manufacture of modern electronics, optoelectronics and sensorics devices. It should also be noted that the technology of magnetron sputtering (installation "Cathode-1M") is highly productive, energetically efficient and environmentally friendly in comparison with other known technologies for creating semiconductor structures and allows them to be obtained with minimal changes in the technological cycle.

Dielectric Properties of Solid Solutions of BiFeO3 with Pb(Ti, Zr)O3 at High Temperature and High Frequency

1968 ◽  
Vol 39 (1) ◽  
pp. 70-74 ◽  
Author(s):  
Robert T. Smith ◽  
Gary D. Achenbach ◽  
Robert Gerson ◽  
W. J. James
Keyword(s):  
High Temperature ◽  
Dielectric Properties ◽  
Solid Solutions ◽  
High Frequency

High frequency dielectric properties of thin-film PZT capacitors

1995 ◽  
Vol 10 (1-4) ◽  
pp. 335-342 ◽  
Author(s):  
W. Williamson Iii ◽  
B. K. Gilbert ◽  
H. D. Chen ◽  
K. R. Udayakumar ◽  
L. E. Cross ◽  
...  
Keyword(s):  
Thin Film ◽  
Dielectric Properties ◽  
High Frequency

A facile method for the preparation of aliphatic main-chain benzoxazine copolymers with high-frequency low dielectric constants

2018 ◽  
Vol 9 (21) ◽  
pp. 2913-2925 ◽  
Author(s):  
Ming Zeng ◽  
Jiangbing Chen ◽  
Qingyu Xu ◽  
Yiwan Huang ◽  
Zijian Feng ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
High Frequency ◽  
Main Chain ◽  
Polymerization Kinetics ◽  
Dielectric Constants ◽  
Low Dielectric

The effects of the reaction solvent on the preparation, polymerization kinetics, and high-frequency dielectric properties of aliphatic main-chain benzoxazine copolymers were investigated.

Effect of ZrO2 on the sintering behavior, strength and high-frequency dielectric properties of electrical ceramic porcelain insulator

2018 ◽  
Vol 5 (1) ◽  
pp. 015202 ◽  
Author(s):  
Niraj Singh Mehta ◽  
Praveen Kumar Sahu ◽  
Md Ershad ◽  
Vipul Saxena ◽  
Ram Pyare ◽  
...  
Keyword(s):  
Dielectric Properties ◽  
High Frequency ◽  
Sintering Behavior ◽  
Porcelain Insulator ◽  
Electrical Ceramic ◽  
Behavior Strength

Photosensitive Polyimide having low loss tangent for RF application

2018 ◽  
Vol 2018 (1) ◽  
pp. 000476-000482 ◽  
Author(s):  
Masao Tomikawa ◽  
Hitoshi Araki ◽  
Yohei Kiuchi ◽  
Akira Shimada
Keyword(s):  
Molecular Structure ◽  
Dielectric Constant ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
High Frequency ◽  
Low Dielectric Constant ◽  
Low Loss ◽  
Elongation At Break ◽  
Low Dielectric ◽  
The Poor

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.

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