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Showing papers on "Insulator (electricity) published in 1980"


Journal ArticleDOI
TL;DR: In this article, a simple model is proposed to explain how a breakdown avalanche of secondary emission electrons can lead to surface flashover when an insulator in vacuum breaks down a few nanoseconds after high voltage is applied.
Abstract: A simple model is proposed to explain how a breakdown avalanche of secondary emission electrons can lead to surface flashover when an insulator in vacuum breaks down a few nanoseconds after high voltage is applied. The case of a plane insulator–vacuum interface perpendicular to parallel electrodes is considered. Positive surface charging is assumed to occur almost immediately upon application of the voltage, and the attendent secondary emission avalanche is assumed to be maintained at saturation throughout the prebreakdown time delay by field emission from the cathode electrode. Bombardment of the insulator by avalanche electrons desorbs a cloud of gas, which is partially ionized as it drifts through the swarm of electrons in the avalanche. The electric field at the cathode end of the insulator becomes enhanced as positive ions accumulate, which in turn increases the field emission and the rates of gas desorption and ionization. This and other regenerative processes rapidly lead to breakdown. Field enhanc...

380 citations


Journal ArticleDOI
L. B. Rothman1
TL;DR: In this article, several commercially available polyimides have been characterized by testing films of them for electric breakdown strength, conductivity, adhesion, and other properties, and the results of these tests are summarized and compared to sputtered.
Abstract: Polyimide is receiving increasing interest as a possible insulator on semiconductor devices, replacing . Several commercially available polyimides have been characterized by testing films of them for electric breakdown strength, conductivity, adhesion, and other properties. The results of these tests are summarized, and the polyimides are compared to sputtered .

139 citations


Journal ArticleDOI
E. A. Cherney1
TL;DR: In this paper, the 60 Hz flashover performance of 230 kV and 500 kV long-rod polymer insulators is compared to standard ceramic suspension insulator strings under moderate ice conditions.
Abstract: The 60 Hz flashover performance of 230 kV and 500 kV long-rod polymer insulators is compared to standard ceramic suspension insulator strings under moderate ice conditions. The tests on clean and heavily pre-contaminated insulators were performed indoors to minimize the effects of wind and temperature variations. In general, contaminated and iced long-rod insulators with disc-shaped sheds of uniform diameter do not perform as well as insulators having conical- shaped sheds of alternating diameters. All 230 kV long-rod insulators tested show an improved performance over conventional ceramic insulation of equivalent length. At 500 kV, only those long-rod polymer insulators that have conical-shaped sheds of alternating diameters show an improved performance over conventional ceramic insulation. A mechanism describing the flashover of contaminated and iced insulators is proposed and discussed in relation to long-rod insulator designs and performance.

89 citations


Patent
16 Sep 1980
TL;DR: In this paper, a printed circuit is manufactured by forming a first conductive circuit pattern on a polished temporary substrate, forming a second circuit pattern (which may be an interconnect pattern) on the first pattern if desired, laminating a flowable insulator material to the first and second conductive circuits, sanding to form a smooth top surface coplanar with the top of the top conductive pattern, selectively adding additional layers and a substrate and stripping the printed circuit from the temporary substrate.
Abstract: A printed circuit which may be highly flexible in configuration and design includes at least one uniformly thick, planar circuit layer including a conductive circuit pattern and an insulating circuit pattern of a cured, flowable insulating material. The printed circuit may include multiple circuit layers that are selectively electrically connected to other layers and may provide circuit patterns, mechanically supportive insulator patterns and windows in almost any desired configuration. The printed circuit may be bonded to a substrate in a high thermal transfer configuration, implemented as a film carrier having plated conductors extending from the surface to receive directly pads of integrated circuit chips or used as a high strength, low coefficient of thermal expansion flexible cable. The printed circuit is manufactured by forming a first conductive circuit pattern on a polished temporary substrate, forming a second conductive circuit pattern (which may be an interconnect pattern) on the first pattern if desired, laminating a flowable insulator material to the first and second conductive circuit layers and temporary substrate to form first and second insulator layers, sanding to form a smooth top surface coplanar with the top of the top conductive pattern, selectively adding additional layers and a substrate and stripping the printed circuit from the temporary substrate. The conductive patterns may be formed with high resolution using photolithographic techniques.

72 citations


Journal ArticleDOI
TL;DR: In this article, the electrical breakdown in a coaxial plasma gun was investigated by means of optical and electrical measurements, and the optimum start and operation conditions of the gun were strongly dependent on material and length of the cylindrical insulator.

39 citations


Journal ArticleDOI
TL;DR: In this article, a simple model was proposed to interpret the switching behavior of metal-polyethyleneterephthalate (PET) metal capacitors as a function of the variables: excitation rate, applied electric field, film thickness, and metal work function.
Abstract: Reversible changes (switching) in the magnitude of the leakage current through a metal‐insulator‐metal (semiconductor) structure can be induced by the excitation of electron‐hole pairs in the insulator. The switching behavior in metal‐polyethyleneterephthalate (PET) metal capacitors is given as a function of the variables: excitation rate, applied electric field, film thickness, and metal work function. The switching is interpreted by a simple model which requires knowledge of the bulk transport of electrons and holes in the insulator, and a high density of hole (or electron) traps near the contact only. The switching occurs when the trapped space charge induces injection from the contact, and saturation is achieved by recombination of the injected carriers with the trapped carriers. Both the time dependence and magnitude of switching is predicted for published switching data in MOS devices with good agreement. Since the model requires knowledge of the current‐voltage characteristic for the contact in que...

33 citations


Patent
31 Jul 1980
TL;DR: In this paper, a high voltage insulator has an optical fiber fed through a channel between intermediate layers in the construction enabling a signal to be applied to or output from the high voltage conductors.
Abstract: A high voltage insulator has an optical fibre fed through a channel between intermediate layers in the construction enabling a signal to be applied to or output from the high voltage conductors. The optical fibre is used to transmit or receive data or voice signals. The optical fibre (12) is flexible and fed through a bore hole (11) in the intermediate constructional layer (8) between core (7) and outer (6) of the insulator (13). Signals are introduced into and received from the optical fibre by photo-elements at the bottom of the insulator and the top in the high voltage connection area. The optical fibre is either glass or a medium wiht similar properties to glass.

32 citations


Patent
04 Mar 1980
TL;DR: A very thin insulator having a dipole structure such as a dielectric material having ferroelectric, pyroelectric and or thermodielectric properties, is used as the insulator insulating an electrode of an electrode pair from a semiconductor body sandwiched between said electrode pair forming a MIS structure as discussed by the authors.
Abstract: A very thin insulator having a dipole structure such as a dielectric material having ferroelectric, pyroelectric and or thermodielectric properties, is used as the insulator insulating an electrode of an electrode pair from a semiconductor body sandwiched between said electrode pair forming a MIS structure. Radiation and solar energy conversion systems based on establishment of an inversion layer by the thermally released bound charges of a polarizable dielectric layer or an electret and irradation of the semiconductor to separate the electron-hole pairs and subsequent collection of mobile carriers. Since there is no metalurgical junction, the generated carriers are not junction limited therefore the generated voltage could be higher than in an ordinary junction solar cell and could also be, an alternating current voltage which can be transformed or rectified.

32 citations


Patent
Dimaria Donelli J1, Donald R Young1
25 Jul 1980
TL;DR: In this paper, a graded oxide MIM or MIS structure employs band gap grading of the insulator oxide so that holes or electrons can be injected into the oxide under moderate electric field conditions from the contact at one interface.
Abstract: A graded oxide MIM or MIS structure employs band gap grading of the insulator oxide so that holes or electrons (depending on voltage bias) can be injected into the insulator oxide under moderate electric field conditions from the contact at one interface. Electron or hole injection from the opposite interface is blocked due to the larger insulator band gap near this interface. A graded oxide metal-silicon dioxide-silicon (MGOS) semiconductor structure may be fabricated by forming several pyrolytic or CVD SiO2 layers over a relatively thick thermal SiO2 layer, with the pyrolytic SiO2 layers having sequentially increasing excess Si content. This structure may also be fabricated by controlled Si ion implantation in the thermal SiO2 layer.

31 citations


Journal ArticleDOI
TL;DR: In this article, a study of the longitudinal loads on a suspension tower and the dynamic response of a transmission line following a broken conductor or dropped insulator is presented, where a new technique for calculating the maximum impact load based upon the conservation of energy is explained.
Abstract: A review of a study of the longitudinal loads on a suspension tower and the dynamic response of aans- transmission line following a broken conductor or dropped insulator is presented. Included are the results of full-scale tests conducted on an existing electric transmission line. A new technique for calculating the maximum impact load based upon the conservation of energy is explained. Predicted values of the peak force using this technique are compared to the recorded test values and published data.

31 citations


Journal ArticleDOI
TL;DR: In this article, the authors used the Kerr and Pockels effects to determine the mechanisms associated with fast insulator flashover in vacuum, and found that the surface field near the cathode is enhanced and the field near anode is reduced during the excitation.
Abstract: Electrooptical measurements of the electric fields along insulator surfaces have been made, utilizing the Kerr and Pockels effects, to determine the mechanisms associated with fast insulator flashover in vacuum. Data are presented that show the temporal and spatial variations of the surface fields prior to and at flashover for insulator surfaces oriented at 0° and 45° with respect to the applied field. It is found that the surface field near the cathode is enhanced and the field near the anode is reduced during the excitation. The results further show a temporal reduction in the field nonuniformity as flashover is approached. The field collapse associated with flashover occurs very rapidly for 0° surfaces. The field collapse for 45° surfaces begins at the anode and propagates at 0.83 cm/ns towards the cathode. Mechanisms consistent with these experimental measurements are postulated.

Patent
10 Jan 1980
TL;DR: In this paper, a method for predicting certain electrical failures in a semiconductor device after long-term operation, including the steps of measuring a predetermined parameter of the semiconductor devices before and after it is exposed to a corona discharge and then comparing the two measurements, is presented.
Abstract: A method for predicting certain electrical failures in a semiconductor device after long-term operation, includes the steps of measuring a predetermined parameter of the semiconductor device before and after it is exposed to a corona discharge and then comparing the two measurements.

Patent
14 Nov 1980
TL;DR: In this article, a frame is insulated from an electric resistance heater coil by insulated supports mounted within beam members of the frame and the supports incorporate structural features enabling the use of simplified supporting beams.
Abstract: An electric heater incorporating simple support structure therefor. A frame is insulated from an electric resistance heater coil by insulated supports mounted within beam members of the frame. The supports incorporate structural features enabling the use of simplified supporting beams. The support insulators include additional structural features for retaining the resistance wire in place and for simplified engagement therewith. The insulators may project on both sides of the support beams and retain heater wires in two planes. The support insulators further provide an integrated structure easily fabricated and simply assembled to the frame.

Patent
12 Jun 1980
TL;DR: A plasma jet ignition plug comprises an electric insulator formed with a discharge cavity and a plurality of electrodes communicating with the discharge cavity to form a spark gap as discussed by the authors, which is formed by a jet opening.
Abstract: A plasma jet ignition plug comprises an electric insulator formed with a discharge cavity and a plurality of electrodes communicating with the discharge cavity to form, within the discharge cavity, a spark gap. The plurality of electrodes include a central electrode connected to a high voltage electric source and a low voltage electric source, and a peripheral electrode which is grounded. The peripheral electrode substantially closes the discharge cavity and is formed with a jet opening. At least that part of at least one of the plurality of electrodes which communicates with the discharge cavity is made of a material selected from a group consisting of ferrite, a nickel alloy containing at least one of silicon, aluminum and magnesium, and electrically conductive ceramic.

Patent
27 Oct 1980
TL;DR: In this paper, a fiberglass rod with mounted metal hardware at each end and juxtaposed polymer sheds strung thereon was used for high voltage application, which reduced the level of generated radio noise and eliminated the corona.
Abstract: This disclosure teaches a suspension insulator comprised typically of a fiberglass rod with mounted metal hardware at each end and juxtaposed polymer sheds strung thereon, which insulator has been improved for high voltage application. Above system voltages of about 138 kV, undesirable radio noise and corona occurs in the area of the metal hardware in conventional designs. Addition of semiconducting polymers between the metal hardward and the polymer sheds significantly reduces the level of generated radio noise and eliminates the corona.

Journal ArticleDOI
TL;DR: In this paper, an experimental procedure, which maintains an almost constant electric field at the insulator-silicon interface, is used to study the trapping of electrons injected into the Aluminum-oxide gate insulator of a MISFET structure.
Abstract: An experimental procedure, which maintains an almost constant electric field at the insulator-silicon interface, is used to study the trapping of electrons injected into the Aluminum-oxide gate insulator of a MISFET structure. A simple model, consisting of a finite number of traps, located at or adjacent to the insulator-silicon interface is consistent with the experimental observations. Additional experiments in which the insulator current is measured directly allow the capture parameter of these traps to be calculated.

Patent
17 Dec 1980
TL;DR: In this article, a safe electroexplosive device such as an electric match is provided by cring the existing electric match with a coating that prevents electrostatic discharge penetration of the coating.
Abstract: A safe electroexplosive device such as an electric match is provided by cring the existing electric match with a coating that prevents electrostatic discharge penetration of the coating. The coating may be either an inner insulator with a conductive outer layer or it may be just a conductive layer over the match. Use of the insulator coating allows an open-circuit terminal to remain once the device is initiated by its power source. Use of only the conductive coat requires the coat to have a resistance greater than the match bridgewire circuit resistance and leaves a low resistance path across the power source after the device has been fired.

Journal ArticleDOI
TL;DR: In this paper, the authors show that the intergap electric field is modified in a manner consistent with positive surface charging by field emitted electrons, and that the enhanced intergap fields are reduced prior to flashover.
Abstract: Electro‐optical measurements of the electric field along solid insulator/vacuum interfaces have been made to determine the mechanisms associated with fast (ns) insulator flashover. Data showing the temporal and spatial performance of the insulator surface fields prior to and at flashover are presented. The results show that the intergap electric field is modified in a manner consistent with positive surface charging by field emitted electrons. The data also show that the enhanced intergap fields are reduced prior to flashover. Mechanisms consistent with this behavior are postulated.

Journal ArticleDOI
TL;DR: In this article, the electric properties of metal-sapphire-silicon transistors are described and the insulator of the devices is obtained by thinning to 50-100 μm the sapphire substrate of s.m.o.s. transistors.
Abstract: Electric characteristics of metal-sapphire-silicon transistors are presented. The insulator of the devices is obtained by thinning to 50–100 μm the sapphire substrate of s.o.s. m.o.s. transistors. Devices allow the determination of electronic mobility μn = 40 cm2 V−1 s−1, in the inversion layer of the Si-sapphire interface.


Patent
29 Jan 1980
TL;DR: In this article, the authors proposed a method to measure the true value of the breakdown voltage of an insulating film by charging an insulator whit positive or negative charges due to the corona discharge and by metering the charge potential with the use of a surface potentiometer.
Abstract: PURPOSE:To make it possible to meter the true value of the breakdown voltage of an insulating film by charging an insulator whit positive or negative charges due to the corona discharge and by metering the charge potential with the use of a surface potentiometer. CONSTITUTION:In case the breakdown voltage of a film 2 of SiO2 which is formed on a P type semiconductor wafer of Si, the Si wafer 1 formed with the film 2 is placed on a test table and is stored with positive (or negative) charges due to the corona discharge. The charges stored on the insulating film can be manually or automatically measured with the use of a surface potentiometer. Thus, the charge storages are repeated, and the storages are repeated on the film of SiO2 so that the maximum potential to be stored on the film of SiO2 becomes the potential value, which can be endured at the most under the condition with no current flowing through the insulating film, i.e., the direct value of the breakdown voltage.

Patent
04 Dec 1980
TL;DR: In this article, the authors describe an insulation arrangement in which a sheath (2) having at least one thin deformable wall (3), for example of foil, contains a powder insulating material, with a high vacuum within the sheath.
Abstract: An insulation arrangement in which a sheath (2) having at least one thin deformable wall (3), for example of foil, contains a powder insulating material (10), with a high vacuum within the sheath. The vacuum can be drawn through an opening (8) after a filter (9) is inserted to prevent removing the powder when the vacuum is drawn. The insulation arrangement can take the form of a panel or a pipe, and the thin wall (3) can be mechanically deformed after the vacuum is drawn.

Journal ArticleDOI
TL;DR: In this article, a test method for evaluation of solid insulating material for insulators in Compressed Gas Insulated Transmission (CGIT) systems has been developed, which measures the ability of an insulating surface to withstand voltage after being subjected to a high energy power arc across its surface.
Abstract: A test method for evaluation of solid insulating material for insulators in Compressed Gas Insulated Transmission (CGIT) systems has been developed. The test measures the ability of an insulating surface to withstand voltage after being subjected to a high energy power arc across its surface. The test has been used to evaluate several different solid insulators in SF6 at 0.4 MPa. The test circuit is designed to effect an efficient transfer of energy from a capacitor bank to an arc on the insulator surface. Voltage reversals in the capacitor bank are minimized. Flash-over of the insulator is initiated using an impulse generator. After exposing the insulator to the arc, the power frequency flash-over voltage is used as a relative measure of the ability of the material to withstand power arcs. The test circuit, sample geometry and representative measurements are described. Epoxy systems with the best performance in these tests showed little or no decrease in power-frequency flash-over voltage after arcing, while large reducitons were observed in other epoxies after only a few power arc-overs. This arc damage test was developed as part of an ERDA Contract to develop a prototype 1200 kV CGIT system.

Patent
17 Mar 1980
TL;DR: In this paper, a multiplex-winding coil with excellent quality is obtained by simultaneously satisfying the functions of interphase insulators and end-portion insulators by lap winding a tape-like insulator.
Abstract: PURPOSE:To obtain this multiplex-winding coil with excellent quality, by simultaneously satisfying the functions of interphase insulators and end-portion insulators by lap winding a tape-like insulator CONSTITUTION:A lead portion 2a is formed by pulling out a nose of a wire 2 in the axial direction on an outer circumference of an insulating cylinder 1, and the wire 2 is lining-up wound on the outer circumference of the insulating cylinder 1 while using the lead portion as a winding starting terminal The wire 2 each moves to upper layers at the end portions of each layer and is concentrically wound, and an end terminal is molded in the same manner as the starting terminal and made up as a lead portion 2d Insulating layers, which are gained by lapping two streaks of tape-like insulators 6a, 6b with width larger than the width of the wire in fixed width so that the progress directions in case of the winding be made differ, are installed among each layer, and function as interphase insulators At the same time, the insulators 6a, 6b are lapped by means of coil winding wires, and also fulfill their functions of end-portion insulators, An outer-circumference insulator is built up by also lapping the insulator 6a or 6b on the outermost layer in fixed width

Patent
27 Nov 1980

Journal ArticleDOI
TL;DR: In this article, it was shown that the correct high field current/voltage characteristic in space charge limited single-injection solid state diodes is obtained at sufficient high fields.
Abstract: It is shown that the correct high field current/voltage characteristic in space charge limited single-injection solid state diodes is obtained at sufficient high fields.

Journal ArticleDOI
TL;DR: In this paper, the authors show that frequency dependent dielectric losses contribute to critical power densities Pk1 and Pk2 independently and equally to resistive losses in the insulating materials which are characterized by a spatially inhomogeneous charger carrier transport.
Abstract: Experimental studies of conduction processes in various insulators at dc and ac voltages up to 50 kHz show that frequency dependent dielectric losses contribute to critical power densities Pk1 and Pk2 independently and equally to resistive losses in the insulating materials which arehar characterized by a spatially inhomogeneous charger carrier transport. The upper critical power density Pk2 marks the transition of the insulator into the prebreakdown state, since thermal equilibrium is no longer conserved. The value of Pk2 may be detected experimentally by the observation of shape-changes of current-instabilities. This is possible, however, only below frequency limits fg which are determined for all our samples. The processes of switching of conductivity, for example the Ovshinsky-effect ffect in the case of amorphous semiconductors, are phenomena which are restricted to the prebreakdown own state.

Journal ArticleDOI
TL;DR: In this paper, the authors make estimates of the time required for an insulator or a semiconductor to acquire a given fraction of its thermodynamic equilibrium charge when it is in contact with a metal.

Patent
03 Nov 1980
TL;DR: In this article, a high voltage insulating bushing is provided with a double layer material interposed between preselected windings of the insulating foils, which serves to advantageously distribute the electric field potential throughout the insulator body.
Abstract: A high voltage insulating bushing formed of wound insulating foils is provided with a double layer material interposed between preselected windings of the insulating foils. The double layer material is formed of insulating material which has been laminated with an electrically conductive material, such as aluminum, and serves to advantageously distribute the electric field potential throughout the insulator body. The double layer material is arranged so that the electrically conductive material faces inwardly toward a longitudinal axis of the insulator body. The edges of a double layer foil which are near the outer surface of the insulator body are folded inward to form an edge wherein the electrically conductive material is enclosed within the insulating layer. In some embodiments, voids formed between the insulating foils and the folded edges of the double layer material are filled with an insulating medium, such as SF6 gas.

Patent
06 Oct 1980
TL;DR: In this article, a multilevel integrated circuit with a single layer of metal or other conductive material is used for interconnection and formation of the conductors and/or gate electrodes of one of the conductor layers.
Abstract: This invention pertains to an improved multilevel integrated circuit wherein a single layer of metal or other conductive material is used for interconnection and formation of the conductors and/or gate electrodes of one of the conductor layers. The multilevel integrated circuit of the present invention also includes a thick interlayer insulator which is located between this conductor/interconnect layer and the underlying substrate and lower level conductors to electrically isolate this layer of metal therefrom. The interlayer insulator is not required in the channel region of charge-coupled circuits.