A dielectric is an electrical Insulator electrical insulator that can be Dipolar polarization polarized by an applied electric field . When a dielectric is placed in an electric field, electric charges ... shift from their average equilibrium positions causing dielectric polarization . Because of dielectric ... direction. This creates an internal electric field which reduces the overall field within the dielectric itself. ref name britannica1 If a dielectric is composed of weakly bonded molecules, those .... ref name britannica1 Although the term insulator implies low electrical conduction , dielectric ... called the dielectric constant .The term insulator is generally used to indicate electrical obstruction while the term dielectric is used to indicate the energy storing capacity of the material by means of polarization . A common, yet notable, example of a dielectric is the electrically insulating material between the metallic plates of a capacitor . The polarization of the dielectric by the applied ... Encyclop dia Britannica Dielectric, insulating material or a very poor conductor of electric current ... http www.britannica.com EBchecked topic 162630 dielectric accessdate 2009 08 12 ref The study of dielectric .... ref Arthur R. von Hippel , in his seminal work, Dielectric Materials and Applications , stated ... physics . The term wikt dielectricdielectric was coined by William Whewell from wikt dia dia electric ... susceptibility Main permittivity The electric susceptibility sub e sub of a dielectric material ... of proportionality which may be a tensor relating an electric field E to the induced dielectric ... math chi e 0 math . Dielectric polarization Dielectric polarization redirects here Basic atomic model Image dielectric model.svg right thumb 400px Electric field interaction with an atom under the classical dielectric model. In the classical approach to the dielectric model, a material ... the electric field and the dipole moment that gives rise to the behavior of the dielectric. Note ... more details
Dielectric reluctance is a scalar measurement of a passive dielectric circuit or element within that circuit dependent on voltage and electric induction flux, and this is determined by deriving the ratio of their amplitudes. The units of dielectric reluctance are F sup 1 sup inverse farad s see daraf Ref. 1 3 . math z epsilon frac U Q frac U m Q m math As seen above, dielectric reluctance is represented as lowercase z epsilon . For a dielectric in a dielectric circuit to have no energy losses, the imaginary part of its dielectric reluctance is zero. This constitutes a lossless resistance to electric induction flux, and is therefore real analysis real , not complex analysis complex . This formality is similar to Ohm s Law for a resistive circuit . In dielectric circuits, a dielectric material has a lossless dielectric reluctance equal to math z epsilon frac 1 epsilon epsilon 0 frac l S math Where math l math is the circuit length math S math is the cross section of the circuit element math epsilon epsilon 0 math is the dielectric permeability See also DielectricDielectric complex reluctance General definition of dielectric reluctance that accounts for energy loss References Hippel A. R., Dielectrics and Waves. New York John Wiley, 1954. Popov V. P., The Principles of Theory of Circuits. M. Higher School, 1985, 496 p. In Russian . Karl K pfm ller K pfm ller K. Einf hrung in die theoretische Elektrotechnik, Springer Verlag, 1959. Category Electric and magnetic fields in matter ... more details
Unreferenced stub auto yes date December 2009 Orphan date February 2009 Image Glass is Liquide.jpg thumb Three dielectric interfaces rendered using the shader. Image Seduce Me by DonBertone.jpg thumb A very accurate render using the shader. The Dielectric Physical Phenomenon Shader is a shader used by the LightWave and Mental Ray 3D Rendering computer graphics rendering engines. It is based on a dielectric dielectric model of physics, which describes how electromagnetic fields behave inside materials. The dielectric shader is able to realistically render the behavior of light rays passing through materials with differing refractive index refractive indices , as well as attenuation of the ray as it passes through a material. Dielectric Shader The shader uses Fresnel equations to simulate reflectance and transmittance of light passing through the dielectric interface, as well as using Snell s law to determine the angle of refraction. In addition Beer s law is used to determine absorption of rays passing through dielectric materials. Two types of dielectric interfaces are supported dielectric air between a dielectric material and air. dielectric dielectric between two dielectric materials. Gallery gallery Image Alcool Di VertigoSP.jpg Frosted glass using Dielectric and Spekle bump mapping. Image RGB.jpg Red, green, and blue rings demonstrating Fresnel reflections. Image C S.jpg Solid glass letters with an IOR of 1.333. Image Le doublot.jpg Two solid dielectric objects overlapping to show the refracting effect. gallery Category 3D graphics software Graphics software stub ... more details
Unreferenced date December 2006 A gate dielectric is a dielectric used between the gate and substrate of a field effect transistor . In state of the art processes, the gate dielectric is subject to many constraints, including Electrically clean interface to the substrate low density of quantum state s for electrons High capacitance , to increase the FET transconductance High thickness , to avoid dielectric breakdown and leakage by quantum tunneling . The capacitance and thickness constraints are almost directly opposed to each other. For silicon substrate FETs, the gate dielectric is almost always silicon dioxide called gate oxide , since thermal oxidation thermal oxide has a very clean interface. However, the semiconductor industry is interested in finding alternative materials with higher dielectric constants, which would allow higher capacitance with the same thickness. Further2 High k dielectric See also QBD electronics DEFAULTSORT Gate Dielectric Category Dielectrics Category Semiconductor structures Electronics stub zh ... more details
Image BroadBandDielectricMirror.jpg thumb 300px right Two broadband dielectric mirrors being used in an optics experiment. A dielectric mirror , also known as a Bragg mirror , is a type of a mirror composed of multiple thin film thin layers of dielectric material, typically deposited on a substrate of glass or some other optical material. By careful choice of the type and thickness of the dielectric layers, one can design an optical coating with specified reflectivity at different wavelength s of light . Dielectric mirrors are also used to produce ultra high reflectivity mirrors values of 99.999 or better over a narrow range of wavelengths can be produced using special techniques. Alternatively, they can be made to reflect a broad spectrum of light, such as the entire visible range or the spectrum ... image Dielectric mirror diagram.svg thumb right Diagram of a dielectric mirror. Thin layers ... leads to constructive interference. Dielectric mirrors function based on the Interference wave propagation interference of light reflected from the different layers of dielectric stack. This is the same principle used in multi layer Anti reflective coating anti reflection coatings , which are dielectric stacks which have been designed to minimize rather than maximize reflectivity. Simple dielectric ... incidence, the layers have a thickness of a quarter wavelength. File Dielectric filter tilted.gif thumb right The color transmitted by the dielectric filters shifts when the angle of incident ... light can also be controlled. In the design of dielectric mirrors, an optical transfer matrix method optics transfer matrix method can be used. Dielectric mirrors exhibit Wave plate retardance ... An electron microscope image of an approximately 13 micrometre piece of dielectric mirror being ... dioxide SiO sub 2 sub are visible on the bottom edge. The manufacturing techniques for dielectric ... links http www.mit.edu birge dispersion Fast code for computation of dielectric mirror reflectivity ... more details
A dielectric resonator also dielectric resonator oscillator , DRO is an Electronics electronic component ... by large change in permittivity rather than by a conductor. Dielectric resonators generally consist of a puck of ceramic that has a large dielectric constant and a low dissipation factor . The Resonance resonance frequency is determined by the overall physical dimensions of the puck and the dielectric ... that an infinitely long cylindrical rod made up of dielectric material could serve as a waveguide. ref Lord Rayleigh, On the Passage of Waves Through Tubes, or the Vibration of Dielectric Cylinders ... a dielectric resonator can be thought of as a truncated dielectric rod waveguide, this research was essential for scientific understanding of electromagnetic phenomena in dielectric resonators. In 1939 Robert D. Richtmyer published a study ref R.D. Richtmyer, Dielectric Resonators , J.Appl. Phys., Vol. 10, pp. 391 398, June 1939. ref in which he showed that dielectric structures can act just as metallic cavity resonators. He appropriately named these structures dielectric resonators . Richtmyer ... conditions at the dielectric to air interface. These results were later used in development of Dielectric Resonator Antenna DRA Dielectric Resonator Antenna . Due to World War II , lack of advanced materials and adequate manufacturing techniques, dielectric resonators fell in relative ... frequency electronics and modern communications industry started to take off, dielectric resonators ... and Piere Guillon, Dielectric Resonators, Artech House, Dedham, MA, 1986. ref frequency selective limiter ref Marian W. Pospieszalski, Cylindrical Dielectric Resonators and Their Applications in TEM Line ... and slow wave ref Marian W. Pospieszalski, Cylindrical Dielectric Resonators and Their Applications ... 1979. ref circuits. In addition to cost and size, other advantages that dielectric resonators have .... There is a vast availability of different dielectric resonators on the market today with unloaded ... more details
A liquid dielectric is a dielectric material in liquid state. Its main purpose is to prevent or rapidly quench electric discharge s. Dielectric liquids are used as electrical insulator s in high voltage applications, e.g. transformer s, capacitor s, high voltage cable s, and switchgear namely high voltage switchgear . Its function is to provide electrical insulation , suppress corona discharge corona and arcing , and to serve as a coolant . A good liquid dielectric should have high dielectric strength , high thermal stability and chemical inertness against the construction materials used, non flammability and low toxicity , good heat transfer properties, and low cost. Liquid dielectrics are self healing when an electric breakdown occurs, the discharge channel does not leave a permanent conductive trace in the fluid. The electrical properties tend to be strongly influenced by dissolved gases e.g. oxygen or carbon dioxide , dust, fibers, and especially ionic impurities and moisture . Electrical discharge may cause production of impurities degrading the dielectric s performance. ref name hveng http books.google.com books?id FGowlP lKK8C&pg PA85&dq dielectric liquids&lr &num 50&as brr 3&cd 6 v onepage&q dielectric 20liquids&f false ref Some examples of dielectric liquids are transformer oil , perfluoroalkane s, and purified water . class wikitable sortable Common liquid dielectrics Name Dielectric constant Max. breakdown strength MeV cm Properties Mineral oil 1.0 ref name hveng Flammable. Common type of transformer oil . n Hexane 1.1 1.3 ref name hveng Flammable. Used in some capacitors. n Heptane Flammable. Castor oil 4.7 High dielectric constant. Flammable. Refined and dried castor oil is used in some high voltage capacitor s. Silicone oil 1.0 1.2 ref name hveng More expensive than hydrocarbons. Less flammable. Polychlorinated biphenyl s Formerly used in transformers and capacitors ... 1.42 ref name hveng Cryogenic. See also Dielectric gas References references Category Dielectrics ... more details
In physics , the term dielectric strength has the following meanings Of an insulating material, the maximum ... experiencing failure of its insulating properties. For a given configuration of dielectric material ... the dielectric material can withstand without breakdown The theoretical dielectric strength of a material ..., or even destroys, its insulating capability. Factors affecting apparent dielectric strength it decreases ... geometries of the dielectric insulator and the electrodes with which the electric field is applied, as well as the rate of increase at which the electric field is applied. Because dielectric materials usually contain minute defects, the practical dielectric strength will be a fraction of the intrinsic dielectric strength of an ideal, defect free, material. Dielectric films tend to exhibit greater dielectric strength than thicker samples of the same material. For instance, the dielectric strength ... because of electron tunneling . Multiple layers of thin dielectric films are used where maximum practical dielectric strength is required, such as high voltage capacitor s and pulse transformer s. Since the dielectric strength of gases varies depending on the shape and configuration of the electrodes, it is usually measured as a fraction of the dielectric strength of Nitrogen gas . Dielectric strength ... Dielectric Strength MV m Helium relative to nitrogen ref name CRC CRC Handbook of Chemistry and Physics ... 19.7 Polyethylene ref cite web url http hypertextbook.com facts 2009 CherryXu.shtml title Dielectric ... facts 2007 DashaMulyukova.shtml title Dielectric Strength of Waxed Paper publisher Hypertextbook.com ... 2011 11 08 ref ntsh 60 60 173 Mica ref name CRC ntsh 45 118 Units In SI , the unit of dielectric ... V cm , volt megavolts per meter MV m , and so on. In United States customary units , dielectric ... facts 2000 AliceHong.shtml Dielectric Strength of Air with multiple references http www.isomil.de en thermocouple dielectric strength.htm Dielectric Strength and Insulation Materials of Mineral Insulated ... more details
Dielectric absorption is the name given to the effect by which a capacitor that has been charged for a long ... time delayed dipole discharging, a phenomenon that is also called dielectric relaxation , soakage or battery action . For some dielectric s, such as many polymer films, the resulting volt age may be less ... s. The voltage at the terminals generated by the dielectric absorption may possibly cause problems in the function .... ref http www.designers guide.org Modeling da.pdf Modeling Dielectric Absorption in Capacitors , by Ken Kundert ref Theory Image Diel.gif thumb The random orientations of molecular dipoles in a dielectric ... causes an Electric field electric field to be applied to the Dielectricdielectric between the electrodes ... moments to align with the field direction. This change in the molecular dipoles is called Dielectric Dipolar polarization oriented polarization and also causes heat to be generated, resulting in dielectric ... decay decay exponentially . ref Elliot sound products, 2.1 Dielectric Absorption http sound.westhost.com ... of a capacitor and the subsequent reloading can be repeated several times. Measurement Dielectric ... s. The voltage regained on the capacitor terminals recovery voltage within 15 minutes is the dielectric absorption voltage. The size of the dielectric absorption voltage is specified in relation to the applied voltage in percent and depends on the dielectric material used. It is specified by many ... ref ref AVX, Dielectric Comparison Chart http www.avx.com docs techinfo dielectr.pdf ref ref Holystone, Capacitor Dielectric Comparison, Technical Note 3 http www.holystonecaps.com ... color ABCDEF Type of capacitor Dielectric Absorption Air and vacuum capacitors Not measurable Class ... and safety The voltage at the terminals generated by the dielectric absorption may possibly cause ..., the small dielectric absorption voltage has no influence on the proper electrical function of the circuit ..., the dielectric absorption voltage generated can be a personnel safety risk. ref http www.keith ... more details
Image microwave oven flashon.jpg thumb 300px A microwave oven , which uses dielectric heating to cook food Dielectric heating , also known as electronic heating , Radio frequency RF heating , high frequency ... wave or microwave electromagnetic radiation heats a dielectric material. At higher frequencies, this heating is caused by molecular dipole rotation within the dielectric. At lower frequencies .... RF dielectric heating at intermediate frequencies, due to its greater penetration over microwave ... mechanisms by which this conversion occurs. Dipole rotation is the mechanism normally referred to as dielectric ... dipoles. Dielectric heating involves the heating of electrically insulating materials by dielectric ... efficient dielectric heating, although higher frequences work equally well or better, and in some ... is eventually translated into molecular vibrations and thus into thermal energy. Dielectric heating ... , with the material to be heated acting as the dielectric inside the capacitor. However, actual electrical contact is not necessary for heating a dielectric inside a capacitor, as the electric fields ... plates with the dielectric non conducting material between the plates. Because lower frequency electrical ... fields that depend on slower molecular motion, such as those caused by ion drag. Power Dielectric ... ll omega epsilon math , then dielectric heating is the dominant mechanism of loss of energy from the electromagnetic field into the medium. For dielectric heating, the generated power density per volume ... part of the complex relative permittivity is a measure for the ability of dielectric material to convert ... in dielectric heating The use of high frequency electric fields for heating dielectric materials ..., dated 1937 states This invention relates to heating systems for dielectric materials and the object ... their mass by means of the dielectric loss produced in them when they are subjected to a high voltage ..., RF dielectric heating has been widely tested and is increasingly used as a way to kill pests in certain ... more details
Dielectric elastomers DEs are smart material systems which produce large Strain materials science strains up to 300 Fact date September 2011 and belong to the group of electroactive polymers EAP . Based on their simple working principle dielectric elastomer actuators DEA transform electric energy directly into mechanical work. DE are lightweight, have a high elastic energy density and have been investigated since the late 90 s. Many potential applications exist as prototypes. Every year in spring a SPIE conference takes place in San Diego where the newest research results concerning DEA are exchanged. Image dielectric elastomers.gif framed Working principle of dielectric elastomer actuators. An elastomeric film is coated on both sides with electrodes. The electrodes are connected to a circuit. By applying a voltage math U math the electrostatic pressure math p el math acts. Due to the mechanical compression the elastomer film contracts in the thickness direction and expands in the film plane directions. The elastomer film moves back to its original position when it is short circuited ... , math varepsilon r math is the dielectric constant of the polymer and math z math is the thickness ... have a low stiffness especially when large strains are required The dielectric constant should be high ... in its elongation by the electrode. Configurations Several configurations exist for dielectric ... to increase displacement. Applications Dielectric elastomers offer a wide variety of potential ..., and piezo actuators. And dielectric elastomers can enable actuators to be integrated into applications that were previously infeasible. A list of some applications for dielectric elastomers are Haptic ... Carpi author2 De Rossi author3 Kornbluh author4 Pelrine author5 Sommer Larsen title Dielectric elastomers ... research electroactive polymers Dielectric Elastomer Stack Actuators DESA at Technische Universit t Darmstadt Use dmy dates date September 2010 DEFAULTSORT Dielectric Elastomers Category Smart materials ... more details
Image Dielectric responses.svg thumb right 454px A dielectric permittivity spectrum over a wide range of frequencies. The real and imaginary parts of permittivity are shown, and various processes are depicted ionic and dipolar relaxation, and atomic and electronic resonances at higher energies. From the http www.psrc.usm.edu mauritz dilect.html Dielectric spectroscopy page of the research group of http www.psrc.usm.edu mauritz mauritz.html Dr. Kenneth A. Mauritz . Dielectric spectroscopy sometimes called Electrical impedance impedance spectroscopy , and also known as electrochemical impedance spectroscopy , measures the dielectric properties of a medium as a function of frequency . ref name Kremer F. 2002 Kremer F., Schonhals A., Luck W. Broadband Dielectric Spectroscopy. Springer Verlag, 2002. ref ref Sidorovich A. M., Dielectric Spectrum of Water. Ukrainian Physical Journal, 1984, vol. 29 ..., 1954. ref ref Volkov A. A., Prokhorov A. S., Broadband Dielectric Spectroscopy of Solids. http ... shown by EIS can help identify the rate limiting step. Dielectric mechanisms There are a number of different dielectric mechanisms, connected to the way a studied medium reacts to the applied field see the figure illustration . Each dielectric mechanism is centered around its characteristic frequency, which is the reciprocal of the characteristic time of the process. In general, dielectric mechanisms can be divided into dielectric relaxation relaxation and resonance processes. The most common ... , where charge carriers blocked at inner dielectric boundary layers on the mesoscopic scale or external ... by a considerable distance and therefore make contributions to the dielectric loss that are orders of magnitude larger than the response due to molecular fluctuations. ref name Kremer F. 2002 Dielectric relaxation Dielectric relaxation as a whole is the result of the movement of dipoles dipole relaxation ... Kronig relation Green Kubo relations Electrochemistry Potentiostat References reflist DEFAULTSORT Dielectric ... more details
A dielectric gas , or insulating gas , is a dielectric material in gaseous state. Its main purpose is to prevent or rapidly quench electric discharge in gases electric discharge s. Dielectric gases are used as insulator electrical electrical insulators in high voltage applications, e.g. transformer s, circuit breaker s namely sulfur hexafluoride circuit breaker s , switchgear namely high voltage switchgear , radar waveguide s, A good dielectric gas should have high dielectric strength , high thermal stability and chemical inertness against the construction materials used, non flammability and low toxicity , low boiling point , good heat transfer properties, and low cost. ref name hveng cite book author1 M S Naidu author2 NAIDU M S title High Voltage Engineering url http books.google.com books?id RF MvfqYMagC&pg PA35 accessdate 17 April 2011 date 22 November 1999 publisher McGraw Hill Professional isbn 9780071361088 pages 35 ref The most common dielectric gas is air , due to its ubiquity and low cost. Another commonly used gas is a dry nitrogen . In special cases, e.g., high voltage switches, gases with good dielectric properties and very high breakdown voltage s are needed. Highly electronegative elements, e.g., halogen s, are favored as they rapidly Carrier generation and recombination recombine with the ion s present in the discharge channel. The halogen gases are highly corrosive ... dielectric properties of the gas. Moisture analysis is used for early detection of this. Dielectric ... the dielectric properties of poorer insulators, e.g. helium or nitrogen. ref cite book author Paul ... pages 433 ref Multicomponent gas mixtures can offer superior dielectric properties the optimum mixtures ... used alone. In mixture with SF sub 6 sub somewhat decrases sulfur hexafluoride s dielectric properties ... dielectric properties are fairly good. Perfluoropropane R 218 chem C 3 F 8 2.2 ref name hveng ... vary, though it is mostly 0 C. References reflist Category Dielectrics Category Dielectric gases ... more details
orphan date January 2010 Dielectric breakdown model DBM is a macroscopic mathematical model combining the diffusion limited aggregation model with electric field . It was developed by Niemeyer, Pietronero, and Weismann in 1984. It describes the patterns of dielectric breakdown of solids, liquids, and even gases, explaining the formation of the branching, self similar Lichtenberg figure s. External links http classes.yale.edu fractals Panorama Physics DLA DBM DBM.html Dielectric Breakdown Model Category Electricity phys stub ... more details
Dielectric complex reluctance is a scalar measurement of a passive dielectric circuit or element within that circuit dependent on sinusoidal voltage and sinusoidal electric induction flux, and this is determined by deriving the ratio of their complex effective amplitudes. The units of dielectric complex reluctance are math F 1 math inverse Farads see Daraf Ref. 1 3 . math Z epsilon frac dot U dot Q frac dot U m dot Q m z epsilon e j phi math As seen above, dielectric complex reluctance is a phasor represented as uppercase Z epsilon where math dot U math and math dot U m math represent the voltage complex effective amplitude math dot Q math and math dot Q m math represent the electric induction flux complex effective amplitude math z epsilon math , lowercase z epsilon , is the real part of dielectric reluctance The lossless dielectric reluctance , lowercase z epsilon , is equal to the Absolute value Complex numbers absolute value modulus of the dielectric complex reluctance. The argument distinguishing the lossy dielectric complex reluctance from the lossless dielectric reluctance is equal to the natural number math e math raised to a power equal to math j phi j left beta alpha right math Where math j math is the imaginary number math beta math is the phase of voltage math alpha math is the phase of electric induction flux math phi math is the phase difference The lossy dielectric complex reluctance represents a dielectric circuit element s resistance to not only electric induction flux but also to changes in electric induction flux. When applied to harmonic regimes, this formality is similar to Ohm s Law in ideal AC circuits. In dielectric circuits, a dielectric material has a dielectric complex reluctance equal to math Z epsilon frac 1 dot epsilon epsilon 0 frac l S math ... element math dot epsilon epsilon 0 math is the complex dielectric permeability See also DielectricDielectric reluctance Special definition of dielectric reluctance that does not account for energy ... more details
Unreferenced date October 2006 Dielectric Thermal Analysis DETA , or Dielectric Analysis DEA , is a materials science technique similar to dynamic mechanical analysis except that an oscillating electrical field is used instead of a mechanical force. For investigation of the curing behavior of thermosetting resin systems, composite materials, adhesives and paints, Dielectric Analysis DEA can be used in accordance with ASTM E 2038 or E 2039. The great advantage of DEA is that it can be employed not only on a laboratory scale, but also in process. Measuring Principle In a typical test, the sample is placed in contact with two electrodes the dielectric sensor and a sinusoidal voltage the excitation is applied to one electrode. The resulting sinusoidal current the response is measured at the second electrode. The response signal is attenuated in amplitude and shifted in phase in relation to the mobility of the ions and alignment of the dipoles. Dipoles in the material will attempt to align with the electric field and ions present as impurities will move toward the electrode of opposite polarity. The dielectric properties of permittivity and loss factor are then calculated from this measured amplitude and phase change. DEFAULTSORT Dielectric Thermal Analysis Category Materials science Category Scientific techniques Science stub ... more details
In semiconductor manufacturing, a low dielectric is a material with a small dielectric constant relative to silicon dioxide. Although the proper symbol for the dielectric constant is the Greece Greek letter kappa , in conversation such materials are referred to as being low k low kay rather than low low kappa . Low dielectric material implementation is one of several strategies used to allow continued scaling of microelectronic devices, colloquially referred to as extending Moore s law . In digital electrical network circuits , insulating dielectrics separate the conducting parts wire interconnect s and transistor s from one another. As components have scaled and transistors have got closer together, the insulating dielectrics have thinned to the point where charge build up and crosstalk adversely affect the performance of the device. Replacing the silicon dioxide with a low dielectric of the same thickness reduces parasitic capacitance , enabling faster switching speeds and lower heat dissipation. Low materials The dielectric constant of SiO sub 2 sub , the insulating material used in silicon chips, is 3.9. This number is the ratio of the permittivity of SiO sub 2 sub divided ... dielectric constants but few of them can be suitably integrated into a manufacturing process ... glass, the dielectric constant is lowered from 3.9 to 3.5. ref cite journal doi 10.1016 S0167 9317 01 ... doped silicon dioxide By doping SiO sub 2 sub with carbon, one can lower the dielectric constant ... dioxide dielectric. Voids can have a dielectric constant of nearly 1, thus the dielectric constant of the porous material may be reduced by increasing the porosity of the film. Dielectric constants ... . Spin on silicone based polymeric dielectric There are two kinds of silicone based polymeric dielectric materials, hydrogen silsesquioxane HSQ and methylsilsesquioxane MSQ . See also High k dielectric ... for silicon integrated circuitry DEFAULTSORT Low K Dielectric Category Semiconductor device materials ... more details
A dielectric resonator antenna is a radio antenna radio antenna mostly used at microwave frequencies and higher, that consists of a block of ceramic material of various shapes, the dielectric resonator , mounted on a metal surface, a ground plane . Radio waves are introduced into the inside of the resonator material from the transmitter circuit and bounce back and forth between the resonator walls, forming standing waves . The walls of the resonator are partially transparent to radio waves, and radio power is radiated into space. ref name Huang cite book last Huang first Kao Cheng authorlink coauthors David J. Edwards title Millimetre wave antennas for gigabit wireless communications a practical guide to design and analysis in a system context publisher John Wiley & Sons year 2008 location USA pages 115 121 url http books.google.com books?id G4CggacS5qUC&pg PA115&dq 22dielectric resonator antenna 22&hl en&sa X&ei FeRAT6e IMXhiAL sMUm&ved 0CEwQ6AEwAg v onepage&q 22dielectric 20resonator 20antenna 22&f false doi id isbn 0470515988 ref An advantage of dielectric waveguide antennas is they lack metal parts, which become lossy at high frequencies, dissipating energy. So these antennas can ... frequencies. ref name Huang Dielectric waveguide antennas are used in some compact portable wireless ..., in 1973. Dielectric resonator antennas DRA offer the following attractive features The dimension ... space wavelength and math epsilon r math is the Relative static permittivity dielectric constant ... loss in dielectric resonators. This leads to high radiation efficiency of the antenna. This feature ... varied from a fraction of a percent to about 10 or more by the suitable choice of the dielectric ... modes of a DRA. See also Dielectric waveguide Dielectric wireless receiver References R. K. Mongia, and P. Bhartia, Dielectric Resonator Antennas A Review and General Design Relations for Resonant ... watch?v EXvdruxTDKk Animation of Radiation from a Circularly Tapered Dielectric Waveguide Antenna ... more details
The thermo dielectric effect is the production of electric current s and charge physics charge separation during phase transition . This interesting effect was discovered by Joaquim da Costa Ribeiro in 1944. The Brazil ian physicist observed that solidification and melting of many dielectric s are accompanied by charge separation. A thermo dielectric effect was demonstrated with carnauba wax , naphtalene and paraffin . Charge separation in ice was also expected. This effect was observed during water freezing period, electrical storm effects can be caused by this strange phenomenon . Effect was measured by many researches Bernhard Gross , Armando Dias Tavares , Sergio Mascarenhas etc. C sar Lattes co discoverer of the pion supposed that this was the only effect ever to be discovered entirely in Brasil . References cite journal last Gross first B. title Theory of Thermodielectric effect journal Physical Review volume 94 pages 1545 1551 year 1954 doi 10.1103 PhysRev.94.1545 bibcode 1954PhRv...94.1545G issue 6 cite book url http books.google.com ?id 4FLaZzmP6RIC&pg PA248 title Science in Latin America a history isbn 9780292712713 author1 Salda a, Juan Jos year 2006 External links http dielektrika.kvalitne.cz termojeveng.html Thermodielectric effect measurement States of matter Category Thermodynamics Category Electricity Category Physical phenomena Category Energy conversion interwiki cs Termodielektrick jev ... more details
The term high dielectric refers to a material with a high dielectric constant as compared to silicon dioxide used in semiconductor manufacturing processes which replaces the silicon dioxide gate dielectric .... As transistors have decreased in size, the thickness of the silicon dioxide gate dielectric has ... the silicon dioxide gate dielectric with a high material allows increased gate capacitance without ... 0 A t math Image High k.svg frame right Conventional silicon dioxide gate dielectric structure compared to a potential high k dielectric structure Image FET cross section.png thumbnail Cross section of an N channel MOSFET transistor showing the gate oxide dielectric Where A is the capacitor area is the dielectric constant relative dielectric constant of the material 3.9 for silicon dioxide ... current flowing through the structure as well as improving the gate dielectric Reliability engineering ... dielectric when the underlying channel is in the inverted state V sub G sub is the voltage ... in the channel length or an increase in the gate dielectric capacitance. Materials and considerations Replacing the silicon dioxide gate dielectric with another material adds complexity to the manufacturing ... efforts have focused on finding a material with a requisitely high dielectric constant that can be easily ... using atomic layer deposition . It is expected that defect states in the high k dielectric can influence ... bias thermally stimulated current spectroscopy to ultrathin high dielectric constant insulator film ... formed silicon oxide dielectric is infused with a small amount of nitrogen. The nitride content subtly raises the dielectric constant and is thought to offer other advantages, such as resistance against dopant diffusion through the gate dielectric. In early 2007, Intel announced the deployment ... during dopant activation annealing. NEC Electronics has also announced the use of a HfSiON dielectric ... in the industry by 2010. See also Low k dielectric Silicon germanium Silicon on insulator References ... more details
The Electronic Industries Alliance EIA Class 2 dielectric materials are ceramic dielectric materials used in ceramic practical capacitor capacitors . The EIA Class 2 dielectrics in general are usually based on formulas with high content of barium titanate BT , possibly mixed with other dielectric electroceramics . Due to its piezoelectric properties, they are subject to microphonics . Other oxides added can be the same as used for Class 1 ceramics. Comparison to Class 1 dielectrics In comparison with the EIA Class 1 dielectric s they tend to have severe temperature drift, high dependence of capacitance on applied voltage, high voltage coefficient of dissipation factor, high frequency coefficient of dissipation, and problems with aging due to gradual change of crystal structure. Aging causes gradual exponential loss of capacitance and decrease of dissipation factor . Marking code The EIA three character code is derived from the minimum and maximum temperature limit, and the amount of capacitance change permitted within that range. valign top class wikitable colspan 2 Minimum br temperature X 55 C Y 30 C Z 10 C valign top class wikitable colspan 2 Maximum br temperature 4 65 C 5 85 C 6 105 C 7 125 C 8 150 C 9 200 C class wikitable colspan 2 Capacitance br change permitted A 1.0 B 1.5 C 2.2 D 3.3 E 4.7 F 7.5 L 15 40 P 10 R 15 S 22 T 22 33 U 22 56 V 22 82 ref name avx Cite web url http download.siliconexpert.com pdfs Caps AVX Cy5v.pdf title Y5V Dielectric author AVX work siliconexpert.com format pdf accessdate 2011 October 31 ref Common types Although this code can describe a huge number of possible dielectrics, only a few are commonly manufactured. X5R performs better than other dielectrics, such as Y5V, and permits the construction of physically smaller capacitors than other ..., and timing applications. Has high dielectric constant . It is an EIA Class 2 dielectric. Its variation ... stability. This is equivalent to the IEC code 2E6 . References reflist See also EIA Class 1 dielectric ... more details
Dielectric barrier discharge DBD is the electrical discharge between two electrodes separated by an insulating dielectric barrier. Originally called silent inaudible discharge and also known as ozone production ... Takemoto, Yoshinori Aiura, and TatsushiIgarashi. http www.freepatentsonline.com 5757132.html Dielectric ... and I. Sardja. http ieeexplore.ieee.org xpl freeabs all.jsp?arnumber 166255 Dielectric barrier discharge ... generators to flat television screens history and future potential of dielectric barrier discharges ... charge distributions in Dielectric Barrier Discharges work Publication date 2009 publisher European ... devices can be made in many configurations, typically planar, using parallel plates separated by a dielectric or cylindrical, using coaxial plates with a dielectric tube between them. ref name kraus ... 2001 b007015g.pdf CO sub 2 sub reforming of methane by the combination of dielectric barrier discharges ... In a common coaxial configuration, the dielectric is shaped in the same form as common fluorescent ... walls acting as the dielectric barrier. Due to the atmospheric pressure level, such processes require high energy levels to sustain. Common dielectric materials include glass, quartz, ceramics .... ref cite web url http hal.archives ouvertes.fr docs 00 25 55 61 PDF ajp jp4199707C405.pdf title Dielectric ... on the surface of the dielectric, they discharge in microseconds millionths of a second , leading ... , semiconductor surfaces , that can also act as dielectric barrier, or to modify gases. Since ... pressure. Medicine Dielectric barrier discharges were used to generate relatively large volume ... 423.pdf title Dielectric barrier discharge system with catalytically active porous segment for improvement ... 7855497.html title Dielectric barrier discharge lamp comprising an UV B phosphor publisher Freepatentsonline.com 12 21 2010 accessdate 9 January 2011 ref Industry A dielectric barrier discharge ... wafers. ref Cite web url http www.siliconfareast.com dielectric.htm title Dielectric publisher ... more details
Dielectric wireless receiver is a type of RF front end radiofrequency receiver front end featuring a complete absence of electronic circuitry and metal interconnects. It offers immunity against damage from intense electromagnetic radiation, produced by Electromagnetic pulse EMP and High power microwave HPM sources. This receiver is known as ADNERF an acronym used to signify an A ll D ielectric N on E lectronic R adio F ront End . ADNERF is a type of E lectro M agnetic P ulse Tolerant M i crowave Re ceiver EMPiRe . Background The continuing trend towards reduced feature size and voltage in integrated circuits renders modern electronics highly susceptible to damages caused by High power microwave High Power Microwave High power microwave HPM and other microwave based directed energy sources. These induce high voltage transient surges of thousands of volts which can punch through the gate insulator in the transistor and can destroy the circuit s metal interconnects. To immunize electronic systems against such threats, the soft spots metal and transistor in a conventional receiver front end, must be eliminated. Operation Image ADNERF Concept Schematic.png thumb right 400px Fig. 1 Concept of the photonic assisted all dielectric RF front end technology. An electro optic EO powered dielectric antenna captures the free space RF signal. The embedded optical link provides complete electrical isolation between the air interface and the electronic circuitry, which is located only after the photodetector PD . Image ADNERF design 3D&efield.png thumb 400px right Fig. 2 Details of the receiver ... concept of this photonic assisted all dielectric RF front end technology is shown in Fig. 1. The Dielectric Resonator Antenna DRA in the front end, functions as a concentrator of incoming electromagnetic ... and B. Jalali, All Dielectric Photonic Assisted Radio Front End Technology, Nature Photonics 1 , 535 ..., B. Houshmand, W. H. Steier, and B. Jalali, All dielectric photonics assisted wireless receiver, Optics ... more details
The Electronic Industries Alliance EIA Class 1 dielectric materials are ceramic dielectric materials used in ceramic practical capacitor capacitors of small values typically 5 nF . The EIA Class 1 dielectrics in general are usually based on titanate formulas usually titanium dioxide with calcium titanate with low or zero content of barium titanate due to that low content, their susceptibility to microphonics is low. Cf. EIA Class 2 dielectric . Their dependence on temperature is linear. C0G EIA or NP0 industry spec is the material with the lowest capacitance temperature dependence Negative Positive zero . C0G NP0 dielectrics have the lowest losses, and are used in filters, as timing elements, and for balancing crystal oscillators. Ceramic capacitors tend to have low inductance because of their flat plate construction. Most other types of capacitor are wound and thus inductive. This makes ceramic capacitors well suited to high frequency work, where they are often used as a leadless disc or plate soldered inline with the PCB track. NP0 refers to the shape of the capacitor s temperature coefficient graph how capacitance changes with temperature . NP0 means that the graph is flat and the device is not affected by temperature changes. The C0G NP0 material can be used up to gigahertz frequencies. Common materials are C0G NP0 , P350 , N1000 M3K . The ceramic composition may involve one or more of dielectric electroceramic s materials. There are two naming conventions. The EIA version relies on letter digit letter code for the slope of the temperature capacitance dependence. The industry version uses a N P prefix N for negative, P for positive and the slope coefficient. See the comparison for some common materials EIA M7G C0G B2G U1G P2G R2G S2H T2H U2J P3K R3L Industry P100 NP0 N030 N075 N150 N220 N330 N470 N750 N1500 N2200 The EIA three character code for the material capacitance ... H 60 J 120 K 250 L 500 M 1000 N 2500 See also EIA Class 2 dielectric EIA Standards http my.execpc.com ... more details
dielectric NRD waveguide has been introduced by Yoneyama in 1981. ref T. Yoneyama, S. Nishida, Non radiative dielectric waveguide for millimeter wave integrated circuits, IEEE Trans. Microwave Theory ... it consists of a dielectric rectangular slab of height a and width b, which is placed between two ... wave regions, Proc. IEE, 1959, 106 B, Suppl. 13, p. 47. ref Due to the dielectric slab, the electromagnetic field is confined in the vicinity of the dielectric region, whereas in the outside ... and junctions, and at the same time much attention has to be paid to the adhesion adherence of the dielectric ..., in the dielectric and in the air, respectively Y sub sub and Y sub 0 sub are the associated ... direction math k y frac m pi a math , with m 0, 1, 2, ... These values are the same in the air as in the dielectric ... to be evanescent in the air regions. In the dielectric region, instead, we have math k 2 k o 2 varepsilon ... where k and are the wavenumber and the wavelength, respectively in the dielectric region and math varepsilon r math is the relative dielectric constant . Unlikely k sub xo sub , k sub x sub is real, corresponding to a configuration of standing wave s inside the dielectric region. The wavenumbers ... walls and continuity conditions at the air dielectric interface. Analyzing the possible transverse ... field are not excited. In the dielectric region, instead, we have math lambda frac lambda ... in the dielectric region the modes with m 1 are above cutoff, while the modes with m 2 are below cutoff 1 2 0.72 1 . In the NRD guide, as in the H guide, due to the presence of the dielectric strip ... eff math is the so called effective relative dielectric constant of the guide. The cutoff frequency ... of for any frequency cannot be simply obtained from the cutoff frequency, as it would be for one dielectric ... by the presence of the dielectric slab. Yet, it is known that a propagation mode inside a guiding ... must be the same in the dielectric as in the air regions in order to satisfy the continuity condition ... more details
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