Journal articles: 'Dielectric Properties'

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Chi, Xiaohong, Wenfeng Liu, Shengtao Li, and Xiaohong Zhang. "The Effect of Humidity on Dielectric Properties of PP-Based Nano-Dielectric." Materials 12, no. 9 (April 28, 2019): 1378. http://dx.doi.org/10.3390/ma12091378.

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Nano-dielectrics are sensitive to humidity and easily degraded in damp environment because of the high surface energy of nanoparticles. In order to study the effect of humidity on the dielectric properties of nano-dielectric, polypropylene (PP) was modified by polyolefin elastomer (POE) and nano-SiO2, and the samples with obvious filling concentration were pre-selected by breakdown strength for damp aging. The aging experiments were carried out in different relative humidity. The dielectric properties of new, hygroscopic saturation and samples after drying were measured and analyzed. It is found that the breakdown strength of hygroscopic saturation nano-dielectrics decreased obviously compared with new samples, and it was difficult to recover after drying. The damp degradation resulted in different changing trends of permittivity of PP and nano-dielectric, but there were relaxation loss peaks of water in both of them. The influence of damp degradation on the trap distribution was studied by thermally stimulated depolarization currents (TSDC), and it was found that the traps level introduced by water molecules was different in PP and nano-dielectrics. All experiment results showed that the performance of nano-dielectrics degraded obviously in humid environment, and it was difficult to recover even after complete drying because of the existence of bounded water molecules in nano-dielectrics.

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Blahovec, J. "Dielectric properties of deformed early potatoes." Research in Agricultural Engineering 54, No. 2 (June 24, 2008): 113–22. http://dx.doi.org/10.17221/3104-rae.

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The permittivity of potato tissue was studied during uniaxial compression of cylindrical specimens prepared from two early varieties. Both the real and the imaginary permitivity components were determined repeatedly during the loading and unloading tests. The analysis of the results obtained shows that small differences exist between the permittivity of the late and early potato varieties. The differences are concentrated mainly at frequencies higher than 1 kHz with a maximum between 10 and 100 kHz. The effect of deformation is concentrated into frequencies between 1 and 100 kHz. The effect of deformation on the permittivity values can be divided into reversible and irreversible parts. The results obtained in the loading/unloading tests give some more information on the proportion of both parts.

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Ghule, B., and M. Laad. "Polymer Composites with Improved Dielectric Properties: A Review." Ukrainian Journal of Physics 66, no. 2 (March 4, 2021): 166. http://dx.doi.org/10.15407/ujpe66.2.166.

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Materials exhibiting high dielectric constant (k) values find applications in capacitors, gate dielectrics, dielectric elastomers, energy storage device, while materials with low dielectric constant are required in electronic packaging and other such applications. Traditionally, high k value materials are associated with high dielectric losses, frequency-dependent dielectric behavior, and high loading of a filler. Materials with low k possess a low thermal conductivity. This creates the new challenges in the development of dielectric materials in both kinds of applications. Use of high dielectric constant filler materials increases the dielectric constant. In this study,the factors affecting the dielectric constant and the dielectric strength of polymer composites are explored. The present work aims to study the effect of various parameters affecting the dielectric properties of the materials. The factors selected in this study are the type of a polymer, type of a filler material used, size, shape, loading level and surface modification of a filler material, and method of preparation of the polymer composites. The study is focused on the dielectric enhancement of polymer nanocomposites used in the field of energy storage devices. The results show that the core-shell structured approach for high dielectric constant materials incorporated in a polymer matrix improves the dielectric constant of the polymer composite.

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Yang, Zhijie, Dong Yue, Yuanhang Yao, Jialong Li, Qingguo Chi, Qingguo Chen, Daomin Min, and Yu Feng. "Energy Storage Application of All-Organic Polymer Dielectrics: A Review." Polymers 14, no. 6 (March 14, 2022): 1160. http://dx.doi.org/10.3390/polym14061160.

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With the wide application of energy storage equipment in modern electronic and electrical systems, developing polymer-based dielectric capacitors with high-power density and rapid charge and discharge capabilities has become important. However, there are significant challenges in synergistic optimization of conventional polymer-based composites, specifically in terms of their breakdown and dielectric properties. As the basis of dielectrics, all-organic polymers have become a research hotspot in recent years, showing broad development prospects in the fields of dielectric and energy storage. This paper reviews the research progress of all-organic polymer dielectrics from the perspective of material preparation methods, with emphasis on strategies that enhance both dielectric and energy storage performance. By dividing all-organic polymer dielectrics into linear polymer dielectrics and nonlinear polymer dielectrics, the paper describes the effects of three structures (blending, filling, and multilayer) on the dielectric and energy storage properties of all-organic polymer dielectrics. Based on the above research progress, the energy storage applications of all-organic dielectrics are summarized and their prospects discussed.

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Debnath, S., Prajna P. De, and D. Khastgir. "Ambient Electrical Properties of Mica-Styrene-Butadiene Rubber Composites." Rubber Chemistry and Technology 61, no. 4 (September 1, 1988): 555–67. http://dx.doi.org/10.5254/1.3536202.

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Abstract We have studied the effect of addition of (a) mica, (b) silane coupling agent, and (c) silane-treated mica on the ambient dielectric properties of vulcanized styrene-butadiene rubber. It is observed that both dielectric constant and dielectric loss increase as mica, silane, and silane-treated mica are added. The increase is more pronounced in the case of silane-treated mica than for the untreated mica systems. The observed values of dielectric constants are in close agreement with the calculated ones obtained from different theories of heterogeneous dielectrics. Dielectric strength shows an increasing trend in the presence of mica. At higher mica loading, D.C. conductivity decreases slightly.

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Sahu, Kriti Ranjan, and Udayan De. "Dielectric Properties of Rhombohedral PbNb2O6." Journal of Solid State Physics 2013 (November 7, 2013): 1–9. http://dx.doi.org/10.1155/2013/451563.

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Dielectric materials are needed in many electrical and electronic applications. So, basic characterizations need to be done for all dielectrics. PbNb2O6 (PN) is ferroelectric and piezoelectric only in its orthorhombic phase, with potential high temperature applications. So, its rhombohedral phase, frequently formed as an undesirable impurity in the preparation of orthorhombic PN, has been ignored with respect to possible dielectric characterizations. Here, essentially single phase rhombohedral PN has been prepared, checking structure from XRD Rietveld Analysis, and the real and imaginary parts of permittivity measured in an Impedance Spectrometer (IS) up to ~700∘C and over 20 Hz to 5.5 MHz range, for heating and some cooling runs. Variations, with temperature, of relaxation time constant (τ), AC and DC conductivity, bulk resistance, activation energy and capacitance have been explored from our IS data.

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Zhao, Cuijiao, Xiaonan Wei, Yawen Huang, Jiajun Ma, Ke Cao, Guanjun Chang, and Junxiao Yang. "Preparation and unique dielectric properties of nanoporous materials with well-controlled closed-nanopores." Physical Chemistry Chemical Physics 18, no. 28 (2016): 19183–93. http://dx.doi.org/10.1039/c6cp00465b.

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Although general porous materials have a low dielectric constant, their uncontrollable opened porous structure results in high dielectric loss and poor barrier properties, thus limiting their application as interconnect dielectrics.

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Jie, Wun Shun, Hanisom Abdullah, Norjan Yusof, and Zulkifly Abbas. "Dielectric Properties of Oil Palm Trunk Core." Journal of Clean Energy Technologies 3, no. 6 (2015): 422–27. http://dx.doi.org/10.7763/jocet.2015.v3.235.

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9

U Rafiq, U. Rafiq, M. Hanif M Hanif, and M. Anis ur Rehman and A. Ul Haq M Anis ur Rehman and A Ul Haq. "Enhanced Dielectric Properties of Sintered MgFe1.98Nd0.02O4 Nanoparticles." Journal of the chemical society of pakistan 42, no. 1 (2020): 87. http://dx.doi.org/10.52568/000608.

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Spinal MgFe1.98Nd0.02O4 was prepared by simplified sol-gel method. To measure the dielectric properties samples were sintered from 700-800 oC in the steps of 50 oC. The sample’s phase purity, crystallographic phase and crystallite size was measured by X-ray diffraction method (XRD). The pellets were analyzed in Scanning Electron Microscope for their surface morphology and grain shape. Dielectric properties were measured from 20 Hz to 3 MHz at room temperature. Samples sintered at 750 oC, showed highest value of AC conductivity which indicated that the material is suitable for use in sensors. However, minimum value of dielectric loss factor was obtained at 800 and#176;C which makes it more suitable for antenna applications.

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U Rafiq, U. Rafiq, M. Hanif M Hanif, and M. Anis ur Rehman and A. Ul Haq M Anis ur Rehman and A Ul Haq. "Enhanced Dielectric Properties of Sintered MgFe1.98Nd0.02O4 Nanoparticles." Journal of the chemical society of pakistan 42, no. 1 (2020): 87. http://dx.doi.org/10.52568/000608/jcsp/42.01.2020.

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Spinal MgFe1.98Nd0.02O4 was prepared by simplified sol-gel method. To measure the dielectric properties samples were sintered from 700-800 oC in the steps of 50 oC. The sample’s phase purity, crystallographic phase and crystallite size was measured by X-ray diffraction method (XRD). The pellets were analyzed in Scanning Electron Microscope for their surface morphology and grain shape. Dielectric properties were measured from 20 Hz to 3 MHz at room temperature. Samples sintered at 750 oC, showed highest value of AC conductivity which indicated that the material is suitable for use in sensors. However, minimum value of dielectric loss factor was obtained at 800 and#176;C which makes it more suitable for antenna applications.

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11

Ahmed, Hameed M., and Shuja-Aldeen B. Aziz. "Dielectric Properties of Commercial non-Polar Polymers." Journal of Zankoy Sulaimani - Part A 11, no. 1 (April 10, 2008): 1–8. http://dx.doi.org/10.17656/jzs.10175.

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12

Su, Yipin, Xudong Shen, Zinan Zhao, Bin Wu, and Weiqiu Chen. "Electromechanical Deformations and Bifurcations in Soft Dielectrics: A Review." Materials 17, no. 7 (March 26, 2024): 1499. http://dx.doi.org/10.3390/ma17071499.

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Dielectric elastomers have attracted considerable attention both from academia and industry alike over the last two decades due to their superior mechanical properties. In parallel, research on the mechanical properties of dielectrics has been steadily advancing, including the theoretical, experimental, and numerical aspects. It has been recognized that the electromechanical coupling property of dielectric materials can be utilized to drive deformations in functional devices in a more controllable and intelligent manner. This paper reviews recent advances in the theory of dielectrics, with specific attention focused on the theory proposed by Dorfmann and Ogden. Additionally, we provide examples illustrating the application of this theory to analyze the electromechanical deformations and the associated bifurcations in soft dielectrics. We compared the bifurcations in elastic and dielectric materials and found that only compressive bifurcation modes exist in elastic structures, whereas both compressive and tensile modes coexist in dielectric structures. We summarize two proposed ways to suppress and prevent the tensile bifurcations in dielectric materials. We hope that this literature survey will foster further advancements in the field of the electroelastic theory of soft dielectrics.

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Chaouchi, Ahcéne, Sadia Kennour, Sophie D'Astorg, Sylvain Marinel, and Mohamed Aliouat. "Low temperature sintered ZnTio3 dielectric ceramics with temperature coefficient of dielectric constant near zero." Processing and Application of Ceramics 4, no. 2 (2010): 75–80. http://dx.doi.org/10.2298/pac1002075c.

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ZnTiO3 compound is an attractive dielectric ceramics owing to its interesting dielectric properties in high frequency range (?r = 19, QXf = 30,000GHz, ?? ? + 120 ppm/?C). The structure, microstructure and dielectric properties of sintered ZnTiO3, with a mixture of ZnO-B2O3 glass phase and CuO oxide as sintering aids, have been investigated. For all compounds, the sintering temperature becomes 850?C due to the glass addition. It is also shown that the addition of CuO oxide allows a control of the temperature coefficient of the permittivity (??). This parameter varies from positive to negative values with increasing the CuO content. The ZnTiO3 composition sintered at 850?C with 5 wt.% ZnO-B2O3 glass phase and 2.2 wt.% CuO addition exhibits attractive dielectric properties (?r = 23, tan ? < 10-3 and a temperature coefficient of the dielectric constant near zero, ?? = 3 ppm/?C) at 1 MHz. All these properties lead this system compatible for manufacturing Ag based electrodes multilayer dielectrics devices needed for LTCC application or other multilayer dielectric components. .

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14

Zhang, Jiacheng, Zi Wang, Guoqing Jiang, Huachao Wei, Zongxi Zhang, and Junwen Ren. "Enhanced Thermal Conductivity and Dielectric Properties of Epoxy Composites with Fluorinated Graphene Nanofillers." Nanomaterials 13, no. 16 (August 12, 2023): 2322. http://dx.doi.org/10.3390/nano13162322.

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The demand for high-performance dielectrics has increased due to the rapid development of modern electric power and electronic technology. Composite dielectrics, which can overcome the limitations of traditional single polymers in thermal conductivity, dielectric properties and mechanical performance, have received considerable attention. In this study, we report a multifunctional nanocomposite material fabricated by blending fluorinated graphene (F-graphene) with epoxy resin. The F-graphene/epoxy composite exhibited a high thermal conductivity of 0.3304 W·m−1·K−1 at a low filler loading of 1.0 wt.%, which was 67.63% higher than that of pure epoxy. The composite dielectric also showed high breakdown strength (78.60 kV/mm), high dielectric constant (8.23), low dielectric loss (<0.015) and low AC conductivity (<10−11 S·m−1). Moreover, the composite demonstrated high thermal stability and strong mechanical strength. It is believed that the F-graphene/epoxy composite has outstanding performance in various aspects and can enable the development and manufacturing of advanced electric power and electronic equipment devices.

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Sathyakam, P. Uma, and Partha S. Mallick. "Future Dielectric Materials for CNT Interconnects - Possibilities and Challenges." Journal of Nano Research 52 (May 2018): 21–42. http://dx.doi.org/10.4028/www.scientific.net/jnanor.52.21.

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Carbon nanotube (CNT) interconnects are emerging as the ultimate choice for next generation ultra large scale integrated (ULSI) circuits. Significant progress in precise growth of aligned CNTs and integration of multiwalled CNT interconnects into a test chip make them promising candidates for future nanoelectronic chips. Tremendous research efforts were made on silicon based ultra-low-k dielectrics for Cu interconnects, but, the most recent advancements in polymer based composites as dielectric materials open up fresh challenges in the use of low-k dielectrics for CNT interconnects. This paper reviews the emerging polymer composites like Boron Nitride Nanotubes, Graphene/Polyimide composites, Metal Organic Frameworks and small diameter CNTs. Many reviews are already exists on the synthesis, fabrication, dielectric, mechanical, chemical and thermal properties of these materials. In this review, we have explained the specific properties of these materials and the necessities for integrating them into CNT interconnects to meet the requirements of future IC designers.Keywords: low-k dielectric materials, ultra low-k dielectrics, carbon nanotubes, interconnects, dielectric constant,

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16

Kovalchuk, N. S., A. A. Omelchenko, V. A. Pilipenko, V. A. Solodukha, S. V. Demidovich, V. V. Kolos, V. A. Filipenia, and D. V. Shestovski. "Research of Electrophysical Properties of Thin Gate Dielectrics Obtained by Rapid Thermal Processing Method." Doklady BGUIR 20, no. 4 (June 29, 2022): 44–52. http://dx.doi.org/10.35596/1729-7648-2022-20-4-44-52.

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Researches of the electrophysical characteristics of gate dielectrics obtained by the rapid thermal processing (RTP) method by two-stage and three-stage processes have been carried out. Each photonic processing (stage) was carried out for 12 s at a constant power of halogen lamps and heating the wafers to a maximum temperature of 1250 °C. The first two stages of the process were carried out in an oxygen atmosphere, the third - in nitrogen or a forming gas. It was found that for dielectrics obtained by the process with final processing in a nitrogen atmosphere, the absolute value of the voltage of flat zones is 0.42 V less, than for insulators, formed by a two-stage process. This is the consequence of the elimination of a significant part of the defects, responsible for the presence of Coulomb centers in the dielectric layer. Carrying out photonic processing in anitrogen atmosphere at high temperatures of procedures for proceeding of the restructuring of the structure of the dielectric layer. For insulators obtained by a three-stage process with final processing in N2, an increase in dielectric strength and breakdown voltage by 1 V and 3.3 MV/cm, respectively, is observed in comparison with dielectrics, obtained by a two-stage process. An increase in dielectric strength indicates relaxation of elastic stresses of deformed bonds and compensation for dangling bonds both in the dielectric and at its interface with Si during high-temperature photonic treatment. Passivation by nitrogen atoms of deformations at the dielectric/semiconductor interface will also have a positive effect on the strength of the insulator.

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BOKOV, ALEXEI A., and ZUO-GUANG YE. "DIELECTRIC RELAXATION IN RELAXOR FERROELECTRICS." Journal of Advanced Dielectrics 02, no. 02 (April 2012): 1241010. http://dx.doi.org/10.1142/s2010135x1241010x.

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In this review the dielectric properties of relaxor ferroelectrics are discussed and compared with the properties of normal dielectrics and ferroelectrics. We try to draw a general picture of dielectric relaxation starting from a textbook review of the underlying concepts and pay attention to common behavior of relaxors rather than to the features observed in specific materials. We hope that this general approach is beneficial to those physicists, chemists, material scientists and device engineers who deal with relaxors. Based on the analysis of dielectric properties, a comprehensive definition of relaxors is proposed: relaxors are defined as ferroelectrics in which the maximum in the temperature dependence of static susceptibility occurs within the temperature range of dielectric relaxation, but does not coincide with the temperature of singularity of relaxation time or soft mode frequency.

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Zaid, Hasnah Mohd, Muhammad Adil, and Lee Kean Chuan. "The Effect of Calcination Temperature on Dielectric Properties of ZnO and Al₂O₃ Nanoparticles at Radio Frequencies." Key Engineering Materials 708 (September 2016): 9–13. http://dx.doi.org/10.4028/www.scientific.net/kem.708.9.

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The dielectric properties of ZnO and Al2O3 are dependent upon various factors such as chemical composition, method of synthesis, grain size, particle size distribution and porosity. A low dielectric constant is often desirable for several applications, whilst for enhanced oil recovery application, high loss dielectrics is required rendering the particles as surface-active agent. In this study, the dependence of the dielectric properties on the calcination temperature of ZnO and Al2O3 nanoparticles is determined as a function of two applied radio frequencies of 18.82 MHz and 167.32 MHz. The experimental results indicate that the nanoparticles of different phases can significantly improve the densification and their dielectric properties. Detailed analysis of the results showed that rotational polarization is the major contributor to the enhanced dielectric behavior of the nanoparticles at the applied frequencies.

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Yamada, Yusuke. "Dielectric Properties of Textile Materials: Analytical Approximations and Experimental Measurements—A Review." Textiles 2, no. 1 (January 14, 2022): 50–80. http://dx.doi.org/10.3390/textiles2010004.

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Deciphering how the dielectric properties of textile materials are orchestrated by their internal components has far-reaching implications. For the development of textile-based electronics, which have gained ever-increasing attention for their uniquely combined features of electronics and traditional fabrics, both performance and form factor are critically dependent on the dielectric properties. The knowledge of the dielectric properties of textile materials is thus crucial in successful design and operation of textile-based electronics. While the dielectric properties of textile materials could be estimated to some extent from the compositional profiles, recent studies have identified various additional factors that have also substantial influence. From the viewpoint of materials characterization, such dependence of the dielectric properties of textile materials have given rise to a new possibility—information on various internal components could be, upon successful correlation, extracted by measuring the dielectric properties. In view of these considerable implications, this invited review paper summarizes various fundamental theories and principles related to the dielectric properties of textile materials. In order to provide an imperative basis for uncovering various factors that intricately influence the dielectric properties of textile materials, the foundations of the dielectrics and polarization mechanisms are first recapitulated, followed by an overview on the concept of homogenization and the dielectric mixture theory. The principal advantages, challenges and opportunities in the analytical approximations of the dielectric properties of textile materials are then discussed based on the findings from the recent literature, and finally a variety of characterization methods suitable for measuring the dielectric properties of textile materials are described. It is among the objectives of this paper to build a practical signpost for scientists and engineers in this rapidly evolving, cross-disciplinary field.

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Wei, Peng Fei. "Dielectric Properties of Na₂O Doped Cao-B₂O₃-SiO₂ System Glass-Ceramics." Advanced Materials Research 750-752 (August 2013): 492–96. http://dx.doi.org/10.4028/www.scientific.net/amr.750-752.492.

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The behavior of dielectric and microwave properties against sintering temperature was been carried out on CaO-B2O3-SiO2glass-ceramics with Na2O addition by XRD and SEM. The results show that 0.5 wt.% Na2O addition is advantageous to improve the dielectric and microwave properties due to increasing the major crystalline CaSiO3. With further increasing Na2O content, α-SiO2is the predominant crystalline phase instead of CaSiO3. The CBS glass-ceramics with 0.5 wt.% Na2O sintered at 875°C has a bulk density of 2.51g·cm-3, and which possesses good dielectric properties:εr=6.2,tanδ=1.9×10-3(10 MHz) and low dielectric constant below 2×10-3over a wide frequency range. The proposed dielectrics can find applications in microwave devices, which require low dielectric loss and low dielectric constant.

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Hu, Xueling, Alix Marcelle Sansi Seukep, Velmurugan Senthooran, Lixin Wu, Lei Wang, Chen Zhang, and Jianlei Wang. "Progress of Polymer-Based Dielectric Composites Prepared Using Fused Deposition Modeling 3D Printing." Nanomaterials 13, no. 19 (October 6, 2023): 2711. http://dx.doi.org/10.3390/nano13192711.

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Polymer-based dielectric composites are of great importance in advanced electronic industries and energy storage because of their high dielectric constant, good processability, low weight, and low dielectric loss. FDM (Fused Deposition Modeling) is a greatly accessible additive manufacturing technology, which has a number of applications in the fabrication of RF components, but the unavoidable porosity in FDM 3D-printed materials, which affects the dielectric properties of the materials, and the difficulty of large-scale fabrication of composites by FDM limit its application scope. This study’s main focus is on how the matrix, filler, interface, and FDM 3D printing parameters influence the electrical properties of FDM-printed polymer-based dielectric composites. This review article starts with the fundamental theory of dielectrics. It is followed by a summary of the factors influencing dielectric properties in recent research developments, as well as a projection for the future development of FDM-prepared polymer-based dielectric composites. Finally, improving the comprehensive performance of dielectric composites is an important direction for future development.

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Wagaye, Gebremedhn Wubet. "Performance Investigation of Coaxial Cable with Transmission Line Parameters Based on Lossy Dielectric Medium." Indonesian Journal of Electrical Engineering and Computer Science 11, no. 2 (August 1, 2018): 424. http://dx.doi.org/10.11591/ijeecs.v11.i2.pp424-428.

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<p>This paper presents the analysis of high performance for coaxial cable with transmission line parameters. The modeling for performance of coaxial cable contains many parameters, in this paper will discuss the more effective parameter is the type of dielectric mediums. This analysis of the performance related to dielectric mediums with respect to dielectric losses and its effect upon cable properties, dielectrics versus characteristic impedance, and the attenuation in the coaxial line for different dielectrics. The analysis depends on a simple mathematical model for coaxial cables to test the influence of the insulators (Dielectrics) performance.</p>

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Yokomizo, Satoshi, Takuya Hoshina, Hiroaki Takeda, Katsuya Taniguchi, Youichi Mizuno, Hirokazu Chazono, Osamu Sakurai, and Takaaki Tsurumi. "Evolution of Internal Stress and Influence on Dielectric Properties by Number of Dielectric Layers in MLCC." Key Engineering Materials 445 (July 2010): 31–34. http://dx.doi.org/10.4028/www.scientific.net/kem.445.31.

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We researched the phenomenon that the permittivity of dielectric layers in multilayer ceramic capacitor (MLCC) increases with the number of dielectric layers. Finite element method (FEM) shows that the internal residual stress in MLCC was generated by the difference of thermal expansion coefficient between internal electrodes and dielectric layers. We developed a electric measurement system with applying external stress for understanding the stress influence on dielectric properties. The compressive stress along electric field increased the polarization. The polar nano regions (PNRs) in shell composition dielectrics were easily influenced by stress. Based on these results, the relationship between the number of dielectric layers and their permittivity in MLCCs was explained.

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RATHEE, KANTA, and B. P. MALIK. "STRUCTURAL AND ELECTRICAL PROPERTIES OF TANTALUM PENTAOXIDE (Ta2O5) THIN FILMS – A REVIEW." International Journal of Modern Physics: Conference Series 22 (January 2013): 564–69. http://dx.doi.org/10.1142/s2010194513010672.

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Down scaling of complementary metal oxide semiconductor transistors has put limitations on silicon dioxide to be used as an effective dielectric. It is necessary to replace the SiO 2 with a physically thicker layer of oxides of high dielectric constant. Thus high k dielectrics are used to suppress the existing challenges for CMOS scaling. Many new oxides are being evaluated as gate dielectrics such as Ta2O5 , HfO2 , ZrO2 , La2O3 , HfO2 , TiO2 , Al2O3 , Y2O3 etc but it was soon found that these oxides in many respects have inferior electronic properties to SiO2 . But the the choice alone of suitable metal oxide with high dielectric constant is not sufficient to overcome the scaling challenges. The various deposition techniques and the conditions under which the thin films are deposited plays important role in deciding the structural and electrical properties of the deposited films. This paper discusses in brief the various deposition conditions which are employed to improve the structural and electrical properties of the deposited films.

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Sustaita-Torres, I. A., C. Sifuentes-Gallardo, J. R. Suárez-López, I. Rodríguez-Vargas, and J. Madrigal-Melchor. "Study of the optical properties of dielectric-graphene-dielectric multilayer quasi-periodic structures: Thue-Morse case." MRS Advances 2, no. 49 (2017): 2787–92. http://dx.doi.org/10.1557/adv.2017.546.

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ABSTRACT:Potential applications in optoelectronics had generated a great interest on the study of graphene optical properties. Along with this, graphene has exceptional properties such as high mobility and optical transparency, flexibility, mechanical robustness, etc. Due to these properties, graphene could be used in different devices such as transparent conductors, organic light-emitting diodes, photodetectors, touch screens, saturable absorbers and ultrafast lasers. A transfer-matrix method is used in order to calculate graphene optical properties, such as transmission, and absorption in the infrared region. The quasi-periodic structure consists in intercalated graphene sheets between two consecutives dielectrics. The dielectric materials follow the Thue-Morse sequence (ThMo). The graphene sheets are described by the optical conductivity considering interband and intraband transitions. The structure of the spectra depends strongly on the number of sequence generation, width of the different dielectrics and dielectric permittivity. In our case, the infrared region corresponds to a chemical potential greater thankT. In the calculated spectra, the geometrical properties of the Thue-Morse sequence can be observed. We obtain absorption bands well defined.

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Iqbal, Muhammad Bilal, Abraiz Khattak, Asghar Ali, M. Hassan Raza, Nasim Ullah, Ahmad Aziz Alahmadi, and Adam Khan. "Influence of Ramped Compression on the Dielectric Behavior of the High-Voltage Epoxy Composites." Polymers 13, no. 18 (September 17, 2021): 3150. http://dx.doi.org/10.3390/polym13183150.

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The emergence of micro and nano-based inorganic oxide fillers with optimal filler-loadings further enhances the required insulation characteristics of neat epoxy. During manufacturing and service application, insulators and dielectrics face mechanical stresses which may alter their basic characteristics. Keeping this in mind, the facts’ influence of mechanical stresses and fillers on dielectric properties of polymeric insulators of two epoxy/silica composites were fabricated and thoroughly analyzed for dielectric characteristics under ramped mechanical compressions relative to the unfilled sample. Before compression, epoxy nanocomposites exhibited responses having an average dielectric constant of 7.68 with an average dissipation factor of 0.18. After each compression, dielectric properties of all samples were analyzed. The dissipation factor and the dielectric constant trends of each sample are plotted against a suitable frequency range. It was observed that after the successive compressions up to 25 MPa, the dielectric properties of epoxy micro-silica composites were highly affected, having an average final dielectric constant of 9.65 times that of the uncompressed sample and a dissipation factor of 2.2 times that of the uncompressed sample, and these were recorded.

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Le, Hong Nhung, Rixuan Wang, Benliang Hou, Sehyun Kim, and Juyoung Kim. "Preparation of Low-Temperature Solution-Processed High-κ Gate Dielectrics Using Organic–Inorganic TiO2 Hybrid Nanoparticles." Nanomaterials 14, no. 6 (March 8, 2024): 488. http://dx.doi.org/10.3390/nano14060488.

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Organic–inorganic hybrid dielectric nanomaterials are vital for OTFT applications due to their unique combination of organic dielectric and inorganic properties. Despite the challenges in preparing stable titania (TiO2) nanoparticles, we successfully synthesized colloidally stable organic–inorganic (O-I) TiO2 hybrid nanoparticles using an amphiphilic polymer as a stabilizer through a low-temperature sol–gel process. The resulting O-I TiO2 hybrid sols exhibited long-term stability and formed a high-quality dielectric layer with a high dielectric constant (κ) and minimal leakage current density. We also addressed the effect of the ethylene oxide chain within the hydrophilic segment of the amphiphilic polymer on the dielectric properties of the coating film derived from O-I TiO2 hybrid sols. Using the O-I TiO2 hybrid dielectric layer with excellent insulating properties enhanced the electrical performance of the gate dielectrics, including superior field-effect mobility and stable operation in OTFT devices. We believe that this study provides a reliable method for the preparation of O-I hybrid TiO2 dielectric materials designed to enhance the operational stability and electrical performance of OTFTs.

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Shabgard, Mohammad Reza, Hossein Faraji, Behnam Khosrozade, Hadi Eivazi-Bagheri, and Keivan Amini. "Study the Effects of Dielectric Type on the Machining Characteristics of γ-Ti Al in Electrical Discharge Machining." International Journal of Engineering Research in Africa 33 (November 2017): 40–49. http://dx.doi.org/10.4028/www.scientific.net/jera.33.40.

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The current study surveys the results of using deionized water and kerosene as dielectrics in the machining outputs of γ-TiAl intermetallic compound obtained in electric discharge machining. Influences of these different dielectrics properties on machining speed, tool wear, surface cracks and roughness were compared. Scanning electron microscopy micrographs were prepared to investigate influences of dielectrics on the surface characteristics of electrically discharged samples. Results indicate which by kerosene dielectric; the material removal rate (MRR) is further compared to another one. But deionized water as dielectric causes higher tool wear ratio than kerosene dielectric. Electrical discharged samples in deionized water have higher surface roughness, in addition it contains surface cracks, whereas kerosene dielectric results better surface finish in low pulse current. According to XRD spectra electric discharge machining in deionized water and kerosene dielectrics produces Ti3 Al intermetallic compound on the produced surface.

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Mogbojuri, Gabriel, Shaghayegh Abtahi, Nayanathara Hendeniya, and Boyce Chang. "The Effects of Chain Conformation and Nanostructure on the Dielectric Properties of Polymers." Materials 18, no. 1 (January 5, 2025): 198. https://doi.org/10.3390/ma18010198.

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The dielectric properties of polymers play a pivotal role in the development of advanced materials for energy storage, electronics, and insulation. This review comprehensively explores the critical relationship between polymer chain conformation, nanostructure, and dielectric properties, focusing on parameters such as dielectric constant, dielectric loss, and dielectric breakdown strength. It highlights how factors like chain rigidity, free volume, molecular alignment, and interfacial effects significantly influence dielectric performance. Special emphasis is placed on the impact of nanofillers, molecular weight, crystallinity, and multilayer structures in optimizing these properties. By synthesizing findings from recent experimental and theoretical studies, this review identifies strategies to enhance energy efficiency, reliability, and mechanical stability of polymer-based dielectrics. We also delve into techniques such as electrostatic force microscopy (EFM) and focused ion beam (FIB) milling for characterizing breakdown mechanisms, offering insights into molecular design for next-generation high-performance polymers. Despite considerable progress, critical challenges such as achieving an optimal balance between dielectric permittivity and breakdown strength, understanding nanoscale interfacial phenomena, and scaling these materials for industrial applications persist. These gaps can be addressed by systematic structure–property relations, advanced processing techniques, and environmental studies.

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Song, Jun, Guo Hua Chen, and Yu Tang. "Effect of Gd₂O₃/BaF₂ Addition on Dielectric Behavior and Energy Storage Properties of Strontium Barium Niobate Glass-Ceramics." Key Engineering Materials 633 (November 2014): 422–26. http://dx.doi.org/10.4028/www.scientific.net/kem.633.422.

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SrO–BaO–Nb2O5–B2O3system glass-ceramics with Gd2O3/BaF2addition have been prepared by controlled crystallization method. The effect of Gd2O3/BaF2addition on the phase evolution, dielectric properties and energy storage properties has been investigated. The addition of Gd2O3/BaF2to the glass-ceramics changes the dielectric property and energy storage density. The glass-ceramics with 0.5 mol% Gd2O3and 4.5mol% BaF2heat treated at 850°C/3h possesses a dielectric constant of 125, a breakdown strength of 1055 kV/mm and energy storage density of 6.16J/cm3, which are promising materials for high energy storage density dielectrics.

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Ling, H. C., M. F. Yan, and W. W. Rhodes. "High dielectric constant and small temperature coefficient bismuth-based dielectric compositions." Journal of Materials Research 5, no. 8 (August 1990): 1752–62. http://dx.doi.org/10.1557/jmr.1990.1752.

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We have studied the crystal structure and the dielectric properties of a scries of Bi-based ceramic compositions as a function of compositional variation and sintering temperature. These dielectrics have dielectric constants hetween 70 and 165 and their temperature coefficients are within ±500 × 10−6/°C. The precise temperature coefficient can be controlled via compositional changes such that dielectrics with temperature coefficients within ±50 × 10−6/°C are easily obtainable. The room temperature dissipation factor is smaller than 0.001 or equivalently, the Q value is greater than 1000. The electrical resistivity is greater than 1014 ohm-cm. Furthermore, these dielectrics are sinterable below 960 °C, rendering it possible to use silver or high silver metallization as the internal electrode in making the multilayer ceramic capacitors.

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Liu, Guang, Yuhao Chen, Yang Cui, Lifang Shen, Taiquan Wu, Chen Chen, Yunxia Luo, and Shubin Yan. "Study on the Effect of Electron/Hole Injection on the Energy-Storage Properties of Polymer Dielectrics." Polymers 16, no. 19 (September 28, 2024): 2750. http://dx.doi.org/10.3390/polym16192750.

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As a critical component of electrostatic capacitors, the polymer dielectric directly affects the performance of the capacitor. In this work, Polycarbonate (PC)/Polyvinylidene fluoride (PVDF) asymmetric bilayer polymer dielectrics were prepared, and the influence of different polymer materials’ barrier characteristics on various electrical properties of composite dielectrics was studied by changing the direction of applied electric fields. Research has found that the dielectric constant of a composite dielectric is between PVDF and PC (approximately 4.8 at 10 Hz) and is independent of the relative position of PVDF and PC in the dielectric. However, the relative position of PC and PVDF has a significant impact on the energy-storage characteristics of composite dielectrics. When PVDF comes into contact with the negative electrode, even though PC has a higher hole barrier, the composite dielectric can only withstand a maximum electric-field strength of 400 MV/m, which is much lower than the maximum electric-field strength that pure PC can withstand (520 MV/m), and it only achieves an energy-storage density of 3.7 J/cm3. When the PC comes into contact with the negative electrode, the high electron barrier of the PC effectively suppresses the injection of electrons at the electrode. It can withstand the same electric-field strength as PC (520 MV/m), achieving an energy-storage density of 5.48 J/cm3, which is 1.46 times that of pure PC and 1.64 times that of PVDF. This experiment effectively combined the advantages of PC and PVDF by utilizing the electron/hole barrier of polymer materials to obtain a fully organic dielectric with excellent energy-storage performance.

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Liu, Zhaoting, Jiale Qiao, Chao Liu, and Shuotong Qiao. "High-Energy Density Pure Polyvinylidene Difluoride with the Magnetic Field Modulation of Free-Volume Pore Size and Other Microstructures." Polymers 16, no. 21 (October 24, 2024): 2979. http://dx.doi.org/10.3390/polym16212979.

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PVDF polymer dielectrics, renowned for their ultra-high-power density, ultra-fast response times, remarkable toughness, and lightweight properties, constitute the essential material foundation for the development of dielectric capacitors. Nevertheless, the low-energy density of these dielectrics presents a challenge to the advancement of dielectric capacitors. In this paper, in the process of preparing monolayer pure PVDF dielectric films by the solution casting method, a fixed-direction magnetic field and a rotating magnetic field were introduced in the horizontal direction, respectively, and this investigation explores the impact of magnetic field modulation on the polymer films’ free-volume pore size, grain size, phase structure, dielectric properties, and energy storage capabilities by altering the duration and orientation of the magnetic field’s influence. This study also discusses how microscopic alterations, particularly in the free-volume pore size, affect the macroscopic dielectric properties. Polymer films treated with a magnetic field of constant orientation for 3 min were obtained with the smallest free-volume hole size of 2.91 Å, the highest γ-phase contents of 54.8%, the smallest grain size of 68 Å, the largest electrical displacement of 10.64 and a very high discharge energy density of 12.68 J/cm3 (a 200% enhancement over pure PVDF).

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Buep, Adrian Hugo. "Dielectric properties of binary systems 10. Ideal dielectric behavior and excess dielectric properties." Journal of Molecular Liquids 51, no. 3-4 (March 1992): 279–306. http://dx.doi.org/10.1016/0167-7322(92)80089-z.

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Park, Jae-Hyung, Min-Soo Kang, Dong-Suk Han, Duck-Kyun Choi, and Jong-Wan Park. "Characterization of Mn-Based Self-Forming Barriers on Low-k Samples With or Without UV Curing Treatment." Journal of Nanoscience and Nanotechnology 15, no. 10 (October 1, 2015): 7493–97. http://dx.doi.org/10.1166/jnn.2015.11145.

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In the present work, we report a Cu–Mn alloy as a material for the self-forming barrier process, and we investigated the diffusion barrier properties of the self-formed layer on low-k dielectrics with or without UV curing treatment. Cu alloy films with 3.8 at% Mn were directly deposited onto low-k dielectrics by co-sputtering followed by annealing at various temperatures. The self-formed layers were investigated by transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDS). In order to compare barrier properties between the Mn-based self-formed layer on low-k dielectric with UV curing and the interlayer on low-k dielectric without UV curing, thermal stability was measured at various thermal stress temperatures. Our results indicated that the formation of the barrier at the interface of Cu–Mn alloy/low-k dielectric was enhanced by UV curing due to changes in the porosity and C concentration in the dielectric layer.

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Li, Qi, Feihua Liu, Tiannan Yang, Matthew R. Gadinski, Guangzu Zhang, Long-Qing Chen, and Qing Wang. "Sandwich-structured polymer nanocomposites with high energy density and great charge–discharge efficiency at elevated temperatures." Proceedings of the National Academy of Sciences 113, no. 36 (August 22, 2016): 9995–10000. http://dx.doi.org/10.1073/pnas.1603792113.

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The demand for a new generation of high-temperature dielectric materials toward capacitive energy storage has been driven by the rise of high-power applications such as electric vehicles, aircraft, and pulsed power systems where the power electronics are exposed to elevated temperatures. Polymer dielectrics are characterized by being lightweight, and their scalability, mechanical flexibility, high dielectric strength, and great reliability, but they are limited to relatively low operating temperatures. The existing polymer nanocomposite-based dielectrics with a limited energy density at high temperatures also present a major barrier to achieving significant reductions in size and weight of energy devices. Here we report the sandwich structures as an efficient route to high-temperature dielectric polymer nanocomposites that simultaneously possess high dielectric constant and low dielectric loss. In contrast to the conventional single-layer configuration, the rationally designed sandwich-structured polymer nanocomposites are capable of integrating the complementary properties of spatially organized multicomponents in a synergistic fashion to raise dielectric constant, and subsequently greatly improve discharged energy densities while retaining low loss and high charge–discharge efficiency at elevated temperatures. At 150 °C and 200 MV m−1, an operating condition toward electric vehicle applications, the sandwich-structured polymer nanocomposites outperform the state-of-the-art polymer-based dielectrics in terms of energy density, power density, charge–discharge efficiency, and cyclability. The excellent dielectric and capacitive properties of the polymer nanocomposites may pave a way for widespread applications in modern electronics and power modules where harsh operating conditions are present.

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Pan, Chung-Long, Chun-Hsu Shen, Shih-Hung Lin, and Qi-Zi Lin. "Tunable Microwave Dielectric Properties of Ca0.6La0.8/3TiO3 and Ca0.8Sm0.4/3TiO3-Modified (Mg0.6Zn0.4)0.95Ni0.05TiO3 Ceramics with a Near-Zero Temperature Coefficient." Molecules 26, no. 16 (August 4, 2021): 4715. http://dx.doi.org/10.3390/molecules26164715.

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The microstructures and microwave dielectric properties of (Mg0.6Zn0.4)0.95Ni0.05TiO3 with Ca0.6La0.8/3TiO3 and Ca0.8Sm0.4/3TiO3 additions prepared by the solid-state method has been investigated. The crystallization and microstructures of these two mixed dielectrics were checked by XRD, EDX, BEI, and SEM to demonstrate two phase systems. Furthermore, the tunable dielectric properties can be achieved by adjusting the amounts of Ca0.6La0.8/3TiO3 and Ca0.8Sm0.4/3TiO3 additions, respectively. After optimization of processed parameters, a new dielectric material system 0.88(Mg0.6Zn0.4)0.95Ni0.05TiO3-0.12Ca0.6La0.8/3TiO3 possesses a permittivity (εr) of 24.7, a Qf value of 106,000 (GHz), and a τf value of 3.8 (ppm/°C), with sintering temperature at 1225 °C for 4 h. This dielectric system with a near-zero temperature coefficient and appropriate microwave properties revealed a high potential for high-quality substrates adopted in wireless communication devices.

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38

Chen, Yong, Zhaozhi Li, Huyin Su, Simin Xue, Mengyun Bian, Lingfang Xu, Wanqiang Cao, and Zhaoxiang Huang. "Influence of Ti content and sintering temperature on dielectric properties of Bi4Ti3O12 ceramics." International Journal of Modern Physics B 31, no. 16-19 (July 26, 2017): 1744057. http://dx.doi.org/10.1142/s021797921744057x.

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An ultra-broad working temperature dielectric material, Bi4Ti[Formula: see text]O[Formula: see text]([Formula: see text] = 2.96, 2.98, 3.0, 3.02 and 3.04), prepared by a conventional mixed oxide route was investigated which is supposed to replace lead-containing ceramics for its outstanding dielectric properties. Microstructure and dielectric properties of well-sintered samples (at 1040[Formula: see text]C, 1060[Formula: see text]C, 1080[Formula: see text]C, 1100[Formula: see text]C and 1120[Formula: see text]C) were studied. X-ray diffraction analysis indicated that the new material was in a single Bi-layered perovskite phase. The dielectric constant and dielectric loss at different frequencies (10, 100 and 1000 kHz) were measured at 1100[Formula: see text]C. With the increasing frequency, the dielectric constant decreased and the dielectric loss was almost unchanged. While at 100 kHz, there is the highest relative permittivity ([Formula: see text]) of 2822.8 and the lowest dielectric loss of 0.0040 ([Formula: see text] = 2.98), the Curie temperature ([Formula: see text]) is 668.9[Formula: see text]C. At the frequency of 1 MHz, the highest relative permittivity ([Formula: see text]) is 1115.8 when Ti content is 3.02, and the Curie temperature is 672.2[Formula: see text]C. SEM can explain the results of the dielectric spectrum at different Ti content and sintering temperatures. [Formula: see text] plots show that Bi4Ti3O[Formula: see text] ceramics are a kind of dielectrics. Since it possesses large dielectric constant, low dielectric loss and stable temperature character, this material shows promising applications for the ultra-broad temperature range components, such as high-temperature multilayer ceramic capacitors and microwave ceramics.

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Zhang, Lei, Jiale Mao, Shuang Wang, Yiting Zheng, Xiangdong Liu, and Yonghong Cheng. "Benzoxazine Based High Performance Materials with Low Dielectric Constant: A Review." Current Organic Chemistry 23, no. 7 (July 16, 2019): 809–22. http://dx.doi.org/10.2174/1385272823666190422130917.

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Interlayer dielectrics with low dielectric constant are the key to unlock the high arithmetic speed of integrated circuit, one of the kernels of modern industry. Polybenzoxazine, derived from benzoxazine precursor, is a new generation of phenolic resin that is considered as an ideal potential candidate for electronic materials due to its unique properties. However, for developing higher speed supercomputers, the dielectric property of conventional polybenzoxazine becomes the Achilles’ heel. Fortunately, the versatile design flexibility of benzoxazine chemistry provides the possibility to reduce the dielectric constant of the material. This review focuses on the recent attempts to synthesize low dielectric benzoxazine and the properties of the corresponding polybenzoxazine materials. Methods including fluorination, hydrocarbon introduction, heterocycle generation, molecular weight tailoring, copolymerization and organic-inorganic hybridization are introduced.

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Tomeno, Izumi, and Sadao Matsumura. "Dielectric properties ofLiTaO3." Physical Review B 38, no. 1 (July 1, 1988): 606–14. http://dx.doi.org/10.1103/physrevb.38.606.

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41

Komine, S., and E. Iguchi. "Dielectric properties in." Journal of Physics and Chemistry of Solids 68, no. 8 (August 2007): 1504–7. http://dx.doi.org/10.1016/j.jpcs.2007.03.024.

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Rahman, M. K., M. F. Hossain, Kazi Mohammad Shorowordi, and M. A. Matin. "Effect of Sintering Time on Dielectric Properties of Barium Titanate and Nb Doped Barium Titanate." Applied Mechanics and Materials 860 (December 2016): 129–33. http://dx.doi.org/10.4028/www.scientific.net/amm.860.129.

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Barium titanate (BaTiO3) with its perovskite structure is a promising dielectric material for many applications such as transducers, actuators, high-k dielectrics and multilayer ceramic capacitors (MLCC). In this study, we have investigated the effect of sintering time on dielectric properties of BaTiO3 and Nb-doped BaTiO3. BaTiO3 was doped with 0.3 mol % niobium oxide (Nb2O5). At first, nanosized pure BaTiO3 and Nb2O5 doped BaTiO3 were milled, dried and pressed into pellets to prepare green samples. Then, the samples were sintered at 1275°C for different time periods ranging from 2 to 5 hrs. Single stage sintering was adopted for the densification of prepared samples. Microstructure of the sintered samples was investigated employing Field-emission scanning electron microscope (FESEM). Dielectric properties of the samples were measured using an impedance analyzer. Finally, a correlation was established between the dielectric properties of the sintered samples and their microstructure. Nb has shown to provide strong inhibiting effect after sintering the samples in the range of 2 to 5 hours at 1275°C thereby, resulted in higher dielectric properties of doped BaTiO3 ceramics compared to that of pure BaTiO3. The best room temperature dielectric constant of 7200 was obtained for Nb doped BaTiO3 sintered at 1275°C for five hours. Such improved dielectric constant is attributed to the optimum grain size of about 1 micron at this sintering temperature.

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Silva Neto, L. P., J. O. Rossi, and A. R. Silva. "Applications of PZT Dielectric Ceramics in High-Energy Storage Systems." Materials Science Forum 727-728 (August 2012): 505–10. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.505.

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The barium and strontium titanate (BST) ceramics have been used with great success as excellent dielectrics in the construction of high voltage (HV) commercial ceramic capacitors with reduced dimensions because of their high dielectric constant. However, the main point of this paper is to investigate other type of ceramic known as PZT (Lead Zirconate Titanate) normally used as piezoelectric sensors in industrial applications. The idea herein is to use the PZT ceramics as HV dielectrics for applications in high-energy storage systems by de-poling their piezoelectric properties in order to avoid dielectric damage and losses at high frequencies. For this, de-poled PZT-4 ceramic samples (30 mm × 2 mm) were submitted to HV tests, in which their dielectric breakdown strength and dielectric constant variation with the applied voltage were assessed. These results obtained confirmed the use of PZT in applications that require reasonable dielectric constant stability (< 15 %) with voltage and HV dielectric breakdown (40 kV/cm) for compact high-energy storage devices.

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Maurya, M. K. "Study of Dielectric Properties of Typical Electrical Insulating Materials by Terahertz Wave Spectroscopy." International Journal for Research in Applied Science and Engineering Technology 12, no. 8 (August 31, 2024): 632–40. http://dx.doi.org/10.22214/ijraset.2024.63973.

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Abstract: This research paper uses a special kind of light is called terahertz waves to study the properties of materials that prevent electricity from flowing, like plastics and glass. Dielectrical insulating materials play an important role in the Insulation coordination of electric power systems such as transformers and high Voltage power cable. Dielectric insulating materials are evaluated based on their dielectric constant, dielectric strength, loss tangent, and thermal stability. The dielectric constant determines the material's ability to store electrical energy, while the dielectric strength indicates the maximum electric field the material can withstand without breaking down. The loss tangent measures energy dissipation as heat, which is crucial for minimizing energy losses in electrical systems. Terahertz (THz) wave spectroscopy has emerged as a powerful technique for the non-destructive evaluation of dielectric properties in electrical insulating materials. This study investigates the application of THz time-domain spectroscopy (THz-TDS) for characterizing typical insulating materials such as polyethylene (PE), polytetrafluoroethylene (PTFE), and epoxy resins. This research can help improve the design and performance of electrical devices, making them safer, more efficient, and more reliable.

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Tıraş, Buşra, Sercan Dede, and Filiz Altay. "Dielectric Properties of Foods." Turkish Journal of Agriculture - Food Science and Technology 7, no. 11 (November 22, 2019): 1805. http://dx.doi.org/10.24925/turjaf.v7i11.1805-1816.2650.

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Dielectric properties of materials are used for evaluating their interactions with electromagnetic energy. Dielectric properties of food materials are required for various applications in food industry such as microwave (at 915 or 2450 MHz), radio wave (at 13.56, 27.12 or 40.68 MHz) and magnetic field processing. In order to understand the response of food materials to electromagnetic energy, dielectric parameters must be determined as a function of frequency, temperature, composition and moisture content. In this review, the dielectric properties of different food groups were listed depending on temperature and frequency ranges. In addition to the literature data of dielectric properties, the penetration depths of microwave or radio wave through food groups were calculated. The effects of temperature and composition (mostly moisture content) on dielectric properties depend on the type of the food and sometimes on frequency. However, the effect of frequency is constant; increased frequency decreased dielectric constant, loss factor and penetration depth. The lowest calculated penetration depth belonged to the fish surimi gel as 3.39 mm at microwave frequency whereas they were high generally for fats, oily seeds and flours (max was 372602 mm for corn flour). It appears that dielectric properties of foods should be investigated further depending on the interactions between frequency, temperature and composition. And then, dielectric heating based on the aim of the process can be applied accordingly. Besides, it appears that the moisture content and especially the dipole rotation and the conductivity movements of the molecules in free water content of the food are some of the most critical factors influencing the dielectric properties of food materials.

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Jakub, Lev, and Kumhála František. "Dielectric properties of hops – an effect of bulk density." Research in Agricultural Engineering 63, Special Issue (December 22, 2017): S18—S23. http://dx.doi.org/10.17221/34/2017-rae.

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Continuous detection of basic physical properties of freshly picked and cleaned wet hop cones would be very helpful for better control and automation of harvesting processes. That is why the main aim of this article was to determine the effects of bulk density changes on dielectric properties of freshly picked hop cones. Relative permittivity and loss factor were measured using a newly developed capacitance measuring device. A strong linear correlation between fresh hops relative permittivity and bulk density was found. This finding could be used e.g. for consequent hop drying process control. Significant differences between tested hop varieties were observed for both relative permittivity and loss factor measurements. These differences cannot be explained only by a slightly different moisture content of the measured varieties and ambient temperature changes. Measured material loss factor was only slightly affected by bulk density changes. However, relative permittivity was affected by bulk density changes significantly. These facts could be used for other properties of wet hop cones estimation.

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Lakshmipathi, Chitta, Borra Rajesh Kumar, Kande Sreelekha, and Thota Subba Rao. "Structural, Dielectric Properties and Conduction Mechanism of SrBi4Ti4O15 Ceramics." Indian Journal Of Science And Technology 15, no. 33 (September 5, 2022): 1605——1612. http://dx.doi.org/10.17485/ijst/v15i33.488.

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Nivrtirao, Eknath, Sannakki Nagaraja, Mahantappa B. Ambalgi, and Basavaraja Sannakki. "Dielectric Properties of Cellulose with EC-PVP Polymer Blends." Indian Journal of Applied Research 3, no. 10 (October 1, 2011): 1–3. http://dx.doi.org/10.15373/2249555x/oct2013/125.

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Hrubesh, L. W., L. E. Keene, and V. R. Latorre. "Dielectric properties of aerogels." Journal of Materials Research 8, no. 7 (July 1993): 1736–41. http://dx.doi.org/10.1557/jmr.1993.1736.

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We have measured the real (dielectric constant) and imaginary (loss factor) components of the complex relative permittivity at 298 K using microwave frequencies (2, 10, and 18–40 GHz) for bulk SiO2-aerogels and for two types of organic aerogels, resorcinol-formaldehyde (RF) and melamine-formaldehyde (MF). Measured dielectric constants are found to vary linearly between values of 1.0 and 2.0 for aerogel densities from 10 to 500 kg/m3. For the same range of densities, the measured loss tangents vary linearly between values of 2 × 10−4 and 7 × 10−2. The observed linearity of the dielectric properties with density in aerogels at microwave frequencies shows that their dielectric behavior is more gas-like than solid-like. The dielectric properties of aerogels are shown to be significantly affected by the adsorbed water internal to the bulk material. For example, water accounts for 70% of the dielectric constant and 70% of the loss at microwave frequencies for silica aerogels. Because of their very high porosity, even with the water content, the aerogels are among the few materials exhibiting such low dielectric properties. Our measurements show that aerogels with greater than 99% porosity have dielectric constants less than 1.03; these are the lowest values ever reported for a bulk solid material.

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Tumarkin, A. V., E. N. Sapego, A. G. Gagarin, N. G. Tyurnina, Z. G. Tyurnina, O. Yu Sinelshchikova, and S. I. Sviridov. "Structural and Electrical Properties of Glass-Ceramic Ferroelectric Composite Materials." Journal of the Russian Universities. Radioelectronics 25, no. 3 (June 28, 2022): 86–95. http://dx.doi.org/10.32603/1993-8985-2022-25-3-86-95.

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Introduction. Materials exhibiting high dielectric permittivity are relevant for use in modern ultrahigh-frequency electronics. Among them, ferroelectrics with high dielectric nonlinearity present particular interest. The electrical strength of ferroelectric materials can be increased using modern composite structures based on mixing ferroelectries and linear dielectrics - materials exhibiting simultaneously low dielectric permittivity and high electrical strength. This approach provides for the opportunity of creating new multicomponent materials with previously unattainable properties and adjusting their component composition, inclusion size and electrical properties across a wide range. In this work, on the basis of porous potassium-iron-silicate glass (KFS) obtained by ion exchange, glass-ceramic materials containing barium titanate were synthesized for use at ultrahigh frequencies.Aim. Production of glass composites by low-temperature sintering of pre-synthesized BaTiO3 (BTO) and potassium-iron-silicate glass, as well as characterization of their structural and electrical properties at ultrahigh frequencies (microwave).Materials and methods. The crystal structure and phase composition of the obtained films were studied by X-ray diffraction using a DRON-6 diffractometer by the emission spectral line CuKα1 (λ = 1.5406 Å). The dielectric permittivity (ε) of microwave samples was evaluated by the Nicholson-Ross method at room temperature using an Agilent E4980A LCR-meter.Results. According to X-ray diffraction analysis, the synthesized samples are a mixture of KFS glass, ferroelectric BaTiO3 and dielectric barium polytitanates; the ratio of the latter determines the electrical properties of the composites. Depending on the content of barium titanate, the studied samples demonstrate a dielectric constant from 50 to 270 at a dielectric loss level of 0.1...0.02. The samples subjected to annealing in an oxygen medium showed an increase in dielectric permittivity by 10.25 % and an increase in controllability with a decrease in dielectric losses by an average of two times.Conclusion. The composite composition of 70 wt % BTO /30 wt % KFS was found to be the most promising in terms of structural and electrical properties. This composite showed an increase in dielectric permittivity by 25 % and a significant increase in nonlinearity, at the same time as reducing losses by more than two times as a result of annealing in an oxygen medium.

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Journal articles on the topic 'Dielectric Properties'

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