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Substrate Materials and Properties
Published in Roydn D. Jones, Hybrid Circuit Design and Manufacture, 2020
Dissipation factor is a measure of the electrical loss characteristic of an insulating material and is usually of greatest importance at high frequencies, particularly at microwave frequencies. The dissipation factor is a function of temperature and frequency, increasing with both these variables.
Microwave Radiation in Biocatalysis
Published in Banik Bimal Krishna, Bandyopadhyay Debasish, Advances in Microwave Chemistry, 2018
David E. Q. Jimenez, Lucas Lima Zanin, Irlon M. Ferreira, Yara J. K. Araújo, André L. M. Porto
The heat amount of a material under microwave radiation will depend on its dielectric properties, i.e., the ability of this specific substance to convert electromagnetic energy into heat at a given temperature and frequency. This is determined by the dissipation factor (tan δ) which is measured by the ratio of the dielectric loss factor (εʺ) and the dielectric constant (εʹ) of the substance (tan δ = εʺ/εʹ). The dielectric loss factor measures the efficiency of electromagnetic energy conversion into heat. Thus, the higher the dissipation factor, the greater the substances will be heated under microwave [18, 19]. Polar molecules and ionic solutions can strongly absorb microwave energy to present a permanent dipole moment, and nonpolar solvents, such as hexane, do not heat under microwave radiation [18]. Another important factor is the dielectric constant, which is a measure of molecular polarity.
Overview of Ceramic Interconnect Technolgy
Published in Fred D. Barlow, Aicha Elshabini, Ceramic Interconnect Technology Handbook, 2018
Aicha Elshabini, Gangqiang Wang, Dan Amey
where ω = 2 π f, f is the frequency, Rs is the series resistance, and 1/ω Cs is the capacitive reactance. ∈″ and ∈′ are the imaginary and the real components of the complex permittivity ε*, that is ε* = ∈′ – i ∈″. A low dissipation factor is desired to avoid excessive dielectric losses. The dissipation factor is of the order 0.0001, 0.0012, 0.005, and 0.05% for Al2O3, BeO, AlN, and SiC, respectively. The dissipation factor tan δ varies from 0.0014% for 75% aluminum oxide to 0.00022% for 99% aluminum oxide.
Bovine Serum Albumin-Based Thin-Film Capacitors for Flexible Electronic Applications
Published in IETE Journal of Research, 2022
Prajukta Mukherjee, Aritra Acharyya, Sandipan Mallik
A small value of the dielectric tangent loss is very essential for any MIM capacitor since it predicts the sensitivity of the device. The dielectric tangent loss can be calculated from the expression given by , where G(f) and C(f) denote conductivity and capacitance of the device at a given frequency [45]. The dielectric tangent loss is also known as the dissipation factor. Figure 3 shows the variations of dissipation factor (D) of BSA-based flexible MIM capacitors having three different BSA layer thicknesses such as 1.0, 2.0, and 3.0 µm with frequency at 1.0 V DC bias. It is interesting to observe from Figure 3 that the values of D are significantly smaller in MIM structures having thinner BSA layer thickness. Dissipation factor (D) around 1.0 indicates greater convenience of a MIM capacitor from the usage prospective. It is noteworthy from Figure 3 that the dissipation factors of the MIM capacitor with t = 1.0 µm are very close to 1.0 for the frequencies less or equal to 600 KHz. Therefore, it can be concluded that the thickness of the BSA-layer has to be kept equal or slightly less than 1.0 µm in order to obtain good capacitive action from BSA-based MIM capacitors up to 600 KHz; and the upper frequency limit can even be increased by lowering the thickness of the BSA layer less than 1.0 µm. It is also noteworthy from Figure 3 that the dissipation factor versus frequency curves are slightly non-linear in nature. This non-linear nature arises due to the effect of finite resistance of the electrode, leakage across the boundaries, and the existence of a barrier layer between dielectric film and the surface of the electrode [46].
Achievable Accuracy in Industrial Measurement of Dissipation Factor of Power Capacitors
Published in NCSLI Measure, 2018
The dielectric loss angle of insulating materials is defined for sinusoidal voltages as the angle δ by which the phase difference between applied voltage and the capacitive current through the capacitor deviates from π/2. The dissipation factor is defined as the tangent of the loss angle δ, and is a basic quality parameter for insulating materials [1]. For small values of dissipation factor, it becomes close to the ratio between active power and reactive power. A low dissipation factor is desired both to reduce energy loss, and to reduce heating of the capacitive object, which can have a deleterious effect on its reliability and life expectancy.