Showing papers on "Insulator (electricity) published in 1986"

Some considerations on the electric field induced in insulators by electron bombardment

Abstract: Starting from a simple model of the distributions of charge created in an insulator by bombardment with electrons, the components of the electric field are evaluated by using Maxwell’s equations and image effects. The results are applied to the most common experimental situations: a semi‐infinite sample (i) bounded by a vacuum or (ii) covered by a conducting film, and a sample in the form of a film (iii) unsupported or (iv) covering a conducting substrate. The results are compared to some experimental data concerning, for instance, electromigration and electron‐stimulated desorption. In surface analysis the decay of the Auger signal from ions of opposite charges and the opposite behavior of ions of the same charge are explained. Similar effects observed in electron‐probe microanalysis of glasses are also elucidated. The results concern scanning electron microscopy, transmission electron microscopy, and electron‐beam lithography applied to biological objects, polymers, ceramics, minerals, glasses, and electronic devices. With slight modifications, the same model can be applied to cases of irradiation with ions or x rays. The evolution of the trapped charges with time is suggested, and the need to indicate the electric parameters (e and γ) of the investigated samples is outlined.

A Metal-Insulator-Semiconductor (MIS) Device Using a Ferroelectric Polymer Thin Film in the Gate Insulator

Abstract: A nonvolatile MIS memory device using a ferroelectric polymer thin film in the gate insulator is proposed. In the gate electrode of the device, a ferroelectric polymer thin film is sandwiched between two insulator films to prevent carrier injection into the polymer thin film. Al-SiO2-P (VDF/TrFE)-SiO2-Si capacitors were fabricated to evaluate the basic characteristics of the device by C-V measurement, and ferroelectric polarization reversal was observed in the capacitors. Based on the C-V measurements, MIS transistors were fabricated using a process which virtually self-aligns the effective gate area to the source/drain. It was shown that the MIS transistor could be electrically programmed and erased. The on/off ratio of the transistor was greater than 106.

Coaxial cable connector

Abstract: A coaxial cable connector is provided, which resists radio-frequency breakdown in coaxial cables used in the vacuum of outer space. The connector body surrounds an insulator which includes an easily compressible elastomeric portion. An insulated coaxial cable is prepared so its insulation projects beyond the outer conductor and compresses the elastomeric portion of the connector insulator.

Make-link programming of semiconductor devices using laser-enhanced thermal breakdown of insulator

Abstract: A semiconductor device is programmed by a laser beam which causes an insulator between two conductors on a silicon substrate to be permanently altered, as by breakdown of the insulator. The conductors may be metals such as aluminum or tungsten, and the insulator is a layer of deposited or thermal silicon oxide. The breakdown may be enhanced by voltage applied between the conductors while the laser beam is focused on the structure.

Thin film transistor

Abstract: PURPOSE:To enable to reduce the length of channel without performing a special microscopic processing by a method wheren a high resistance semiconductor thin film, a gate insulating film and a gate electrode are successively formed on the side face where main electrode regions are multilayer-stacked through an insulating film. CONSTITUTION:The first main electrode thin film region 3, an insulating film 17 and the second main electrode thin film region 2 are successively stacked on the surface of a substrate 1 having the surface consisting at least of an insulator, and a high resistance semiconductor thin film 5 is formed on the side face of stacked region 3, film 17 and the region 2 in such a manner that at least both ends of the film 5 come in contact with the regions 2 and 3. A gate electrode 4 is provided on the surface of the thin film 5 through the intermediary of a gate insulating film 6. The channel length of said thin film transistor is mostly determined by the thickness of the film 17, and an arbitrary value can be selected. Especially, a short channel thin film transistor can be accomplished easily. Besides, as no outside light is projected directly on the thin film 5 even when amorphous Si is used for the thin film 5, it is unnecessary that a light-shielding film is provided.

Dual electron injector structures using a conductive oxide between injectors

Abstract: The present invention relates to DEIS (Dual Electron Injector Structure) EAROM (Electrically Alterable Read Only Memory) devices which utilize a silicon-rich, silicon dioxide insulator between injectors which has an excess of silicon therein which is less than the excess of silicon in the silicon rich, silicon dioxide injectors The device does not depart in any way from known DEIS EAROM devices except that the insulator layer between the injectors is rendered conductive to a desired degree by causing a compound insulator like SiO2 to be off-stoichiometry during deposition so that the resulting insulator becomes silicon rich Alternatively, the insulator may be deposited together with another metal which renders the insulator conductive or a metallic specie may be added to the insulator by diffusion or ion implantation after the insulator is formed The resulting conductive insulator provides a means for draining off trapped charge in the insulator resulting in a device of such improved cyclibility that the DEIS EAROM can be used as a Non-Volatile Random Access Memory (NVRAM) capable of from 108 to greater than 1010 cycles before threshold collapse occurs The conductive insulator is designed so that it is conductive only at high electric fields encountered during writing and erasing and highly blocking at low fields encountered during reading or storage operations

Dc power cable

Abstract: PURPOSE:To increase the DC breakdown voltage by providing space charge mitigating layers at least between an inside semiconductive layer and an insulator or between an outside semiconductive layer and the insulator. CONSTITUTION:Space charge mitigating layers 4-7 preventing the accumulation of space charges are provided at least between an inside semiconductive layer 1 located around a conductor N and an insulator 2 or between an outside semiconductive layer 3 and the insulator 2. The space charge mitigating layer 4 is provided between the inside semiconductive layer 1 and the insulator 2, and the space charge mitigating layer 5 is provided between the outside semiconductive layer 3 and the insulator 2, and space charge mitigating layers 6, 7 are provided both between the inside semiconductive layer 1 and the insulator 2 and between the outside semiconductive layer 3 and the insulator 2. The accumulation of space charges giving an adverse effect to the insulator 2 is thereby reduced, and a DC power cable with the high dielectric strength is obtained.

Fault tolerant thin-film photovoltaic cell

Abstract: A thin-film solar cell is made up of semi­conductor layers formed on a substrate. The substrate includes an insulator containing electrically conduc­ting nucleation sites which is interposed between the electrical contact of the substrate and the adjacent semi-conductor. The insulator can also be optically transparent. Grain boundaries and voids terminate on the insulator. The solar cell is fabricated by selec­tively introducing nucleation sites into the insulator layer which is formed on the substrate material, and activating the nucleation sites during growth of the semi-conductor layers.

Flow sensor on insulator

Abstract: A flow sensor on a thermally insulating substrate is provided with improved thermal conductance and ruggedness to hostile environments The flow sensor includes a pn junction temperature sensing element on the substrate, a layer of dielectric material, which provides electric isolation and physical protection, covering the pn junction element, and a thin film heating element covering the dielectric layer and being in close thermal contact with the pn junction element

The Pressure wave Propagation Metod for the Analysis of Insulating Materials: Application to LDPE Used in HV Cables

Abstract: In the field of electrical insulation, polymers are progressively replacing formerly used materials. When such an insulator is subjected to a voltage gradient, an internal space charge and a polarization develop, eventually reducing the apparent electrical strength of the material. We have applied the pressure wave propagation (PWP) method to the study of HV insulators, such as low density polyethylene (LDPE) used for HV cables. The spatial charge distribution is successively measured in samples subjected to various processes. The influence of additives in the development of a space charge under electric stress is directly shown. We have also observed that the nature of the electrode-iinsulator interface strongly affects the charge distribution throughout the insulator, and that charge injection from these interfaces occurs at much lower applied voltage gradients than previously assumed. The evolution in time of the charge distribution in samples submitted to voltage gradients, at 20 and 700C, is studied. These results show that an equilibrium is reached, from which the life expectancy of materials and cables can be evaluated.

Selection and evaluation of insulator materials for high performance railgun bores

Abstract: Both conductor and insulator materials used in railgun bores are major factors in achieving the desired system performance parameters and barrel lifetime. This paper reports the interim results of a systematic effort to review the design requirements, and to select, evaluate, and test candidate insulator materials with the potential to best meet these requirements. Approximately fifteen (15) commercial and advanced insulator materials including organic polymers, reinforced polymers, reinforced glasses, technical ceramics, advanced ceramics and reinforced ceramics are included. Pertinent performance parameters based on material properties are compared to the results of small railgun screening tests. The arc exposures were performed at the U.S. Army Ballistic Research Laboratory. The extent and modes of damage, as determined by detailed pre- and post-test evaluation of the arc-exposed insulator materials, are reported.

Field Optimization of High-Voltage Insulators

Abstract: A method is described for optimizing the field stress on HV insulators by modifying their profile, seeking a uniform distribution of the tangential field along the insulator surface. This results in an increase of the onset voltage for surface flashover and in a significant saving of the space of the HV installation. The optimization process was achieved by an algorithm developed for calculating the tangential field component and mathematical expressions of the profile to be corrected through an iterative procedure. The algorithm was based on a modified charge simulation technique to satisfy a better matching of the boundary conditions to the electrode and insulator surfaces involved in the HV installation. The algorithm is expanded to study the effect of contamination on the tangential field distribution. It is found that the higher the conductivity of the contamination layer, the higher is the field uniformity along the insulator surface.

Impedance matched plug-in package for high speed microwave integrated circuits

Abstract: A TO can-style plug-in package employs a pin/glass interface. In a first embodiment the pin/glass seal interface has a center pin of reduced diameter embedded in a smaller outer diameter, lower dielectric constant glass than a conventional TO-can. The glass is surrounded by a metal ferrule. The metallic header through which the pin/glass interfaces extend is provided with a ridge adjacent to the end of a respective pin. This increase in thickness of the header surrounding each glass-embedded center pin provides a prescribed capacitive reactance component for compensating the inductive reactance of the interiorly extending segment of the center pin and any connecting lead through which the microwave integrated component is coupled to the pin. In a second embodiment, the thickness of insulator glass that surrounds the center conductor is less than the thickness of the header.

Shielded connector system for coaxial cables

Abstract: A coaxial cable termination system, includes a coaxial cable terminator including a coaxial cable having signal and shield conductors and insulation separating the conductors, an electrical contact electrically connected to the signal conductor, the electrical contact having a contacting portion for electrically connecting with an external member inserted to engagement with respect thereto, a protective insulator for covering at least part of the contacting portion, and a strain relief body molded directly to at least part of the coaxial cable, electrical contact and protective insulator for holding the same in relatively fixed positions with respect to each other; and a housing for receiving therein the terminator to hold the same in position to make electrical connectioin with an external member inserted into the housing means to engage the electrical contact.

Photoenhanced Deposition of Silicon Oxide Thin Films Using an Internal Nitrogen Discharge Lamp

Abstract: This paper describes the optical and electrical properties of silicon oxide thin films produced using a novel photoenhanced deposition technique. Since there is no damage to the growing film surface from energetic ions, this process has the potential to produce better semiconductor/insulator interfaces than those grown using conventional RF glow discharge techniques. The deposition system is comprised of a windowless nitrogen discharge lamp contained within the reaction vessel. This unified approach allows the low wavelength UV light from the lamp to couple directly into the reaction gases without attenuation by a window material or the need for mercury sensitisation. Thin films of silicon oxide have been deposited onto single crystal silicon wafer substrates from a nitrous oxide/monosilane reaction gas mixture. The deposition rate and physical properties of films produced in this way are comparable to those of high quality insulator films deposited by plasma enhanced CVD techniques. The results of electrical tests indicate that this material could be used as a low temperature deposited insulator for thin film devices.

The logarithmic response of palladium‐gate metal‐insulator‐silicon field‐effect transistors to hydrogen

Abstract: The response characteristics of palladium‐gate metal‐insulator‐silicon field‐effect transistor (MISFET) structures to hydrogen are shown to be logarithmically related to the partial pressure of the gas. It is proposed that these palladium‐gate MIS structures should be considered as electrochemical devices where the metal/insulator structure behaves as a gas electrode. The results presented were obtained for hydrogen in air and therefore relate directly to the use of these devices as sensors for use in the ambient environment.

Heat cooking apparatus having a flat flexible heater

Abstract: A heat cooking apparatus is provided with a heater comprising a plurality of metal, electric heating wires and a plurality of mica to insulate said wires, which is formed as a flat shape to provide on the outside of the heating chamber with substantially the same area as the ceiling of heating chamber, and which is firmly mounted onto said ceiling of the heating chamber by a heat resistant insulator and a metal keep plate.

Computation of the electric field at a solid/gas interface in the presence of surface and volume charges

Abstract: Enhancement of the electric field at a solid insulator/electrode/gas triple junction and on the surface of an insulator, due to imperfect contacts, surface irregularities and contamination, reduces the withstand voltage of the gas-only system. The charges deposited on the surface and in the bulk of the insulator, when stressed under high voltage, further modify the electric field. In the paper, the influence of accumulated static charges on the electric field distribution associated with a cylindrical insulator held between plane electrodes in atmospheric air is investigated. The electric field along the solid dielectric/air interface is calculated for different surface and volume charge distributions by using the finite-difference method based on Gauss's law. Derivation of the iteration equations are relatively easy, and, unlike most methods, there is no need for external imposition of solid dielectric/gas boundary conditions. The results indicate that, for some surface and volume charge distributions, field enhancement occurs at the triple junction, and this could initiate a surface flashover.

Solid ph sensor

Abstract: PURPOSE:To make construction simple and manufacture easy and to make measurement with large output electric power by using electrodes consisting of different metals and detecting the electric current generated by bringing the two electrodes into contact with an aq. soln. to be measured in the form proportional to pH concn. CONSTITUTION:The electrode of the sensor is formed of the electrodes consisting of the different metals, for example, an Al electrode 1 and Zn electrode 2 and an insulator 3 for insulating both electrodes 1, 2. The current proportional to H ion is generated together with a specified voltage in the circuit when the two electrodes 1, 2 are electrically coupled by bringing the liquid to be measured into contact with the electrodes 1, 2 to form a voltaic cell by the H ion existing in the liquid. The output electric power in this case is read by a DC ammeter A and is measured. The electrode constitution is thus made simple and the manufacture is easy. The output electric power is increased and the measurement is made possible without using an amplifier circuit in some case.

Alternating current circuit breaker with vacuum chamber - sepd. by insulating layer from wall of insulator module

Abstract: An alternating current circuit breaker has a vacuum chamber with an outer wall sepd. from the inner wall of a module mounted on an insulator by an insulating coating, fixed and mobile contacts in the chamber, and an activator for the chamber. The coating is pref. of silicone rubber. USE/ADVANTAGE - Used for a railway. The circuit breaker cannot generate flame, explosion, smoke, or vapour.

Electrode for electric discharge machining and method for producing the same

Abstract: An electrode for electric discharge machining wherein at least a part of the surface of the electrode is coated with a non-single crystalline insulator to prevent undesirable electric discharge between the electrode and a workpiece. The electrode may also have a coating of a buffer material formed from a metal having a small thermal expansion coefficient or from an amorphous material, in which case the exterior coat is a hard insulator with a Vickers hardness of at least 1000 coated on the buffer. A process for the production of these electrodes using plasma discharge methods is also described.

Electric discharge machining for electric insulator

Abstract: PURPOSE: To easily perform the electric discharge machining of ceramic or the like by performing the electric discharge machining is formation of electric conductor on the surface of the electric insulator and forming the conductive layer at high temperature with the carbon and conductive powder in the machining liquid and then repeating the electric discharge machining and the formation of the conductive layer. CONSTITUTION: On the surface of an electric insulator 1 to be machined, a conductive layer 2 is formed by the frame coating, evaporation, plating or the like of copper, iron or the like and the electric discharge machining is started with the supply of the machining liquid such as kerosene between the same and a machining electrode 3. First, the conductive layer 2 is machined so that the electric insulator 1 facing to the conductive layer 2 is exposed. Then machining powder and carbon in the machining liquid are sticked to the electric insulator 1 and further penetrated thereinto and the new conductive layer 4 is formed at the high temperature caused by the electric discharge machining. The electric insulator such as ceramic is machined by repeating the electric discharge machining and the formation of the conductive layer 4. Therefore it is possible to easily perform the electric discharge machining of the electric insulator such as ceramics. COPYRIGHT: (C)1988,JPO&Japio

Computation of Electric Fields and Study of Optimal Corona Suppression for Bushing-Type Insulators

Abstract: Using the Runge-Kutta and Newton-Raphson methods, the electric fileds on the bushing-type insulator surface covered partly by a corona-suppression semiconductor coating with a field-dependent resistivity have been computed for semiconductors having various resistivityfield ield (p-E) characteristics. The field distribution along the insulator surface is strongly dependent on the p-E characteristic and the extension of the semiconductor coating as well as the frequency of the operating voltages. By assigning the highest field along the insulator surface to be the critical field for the onset of corona discharges (or the breakdown strength of air or other medium), the corona inception voltage of the insulators can be evaluated easily. Thus, by the comparison of the field distribution curves, it is easy to determine the type of the p-E characteristic and the extension of the semiconductor coating for optimal corona suppression. For bushing-type insulators, the computed results show that the semiconductors with p = poexp(-BE) or p * pO[2 - exp(aE)], where po, and a are constants, could give optimal corona suppression. The optimal choice depends on the physical parameters of the insulator, the extension of the semiconductor coating and the frequency of the operating voltages, and therefore the constants pO and or a have to be determined for individual cases. In general, for optimal al corona suppression po should decrease with increasing frequency and length of the insulator surface; and or a should increase with increasing length of the insulator surface.

Fiber optic connector epoxy curing apparatus

Abstract: An apparatus for heat curing epoxy banded fiber optic connectors includes a housing containing a heater control circuit and an electronic thermometer An L-shaped jig is attached to a surface of the housing with an interposing insulator A heating element and temperature sensors are connect to the jig

Insulator assembly for electrode of piezoelectric ignition device

Abstract: An insulator assembly for a piezoelectric ignition device includes a Teflon sleeve which surrounds the electrode of the ignition device, a ceramic insulator tube which surrounds the Teflon sleeve, and flexible silicone sealing material between the insulator tube and the piezoelectric crystal and between the insulator tube and the casing for the crystal.

Electrical radiant heater for heating heating surfaces

Abstract: An electric radiant heater (11) for heating a glass ceramic cooking surface (12) contains a dish-shaped insulator (14), to whose inner bottom surface (18) are fixed heater coils (20). The heater coils have an oval cross-section and are pressed by their narrow sides into surface (18) and fixed. The fixing pressing in takes place during the moulding of the moist insulator (14), made from fibrous material and by means of a male mould receiving the heater coils in slots.

Railgun insulator materials test

Abstract: An injected round bore railgun (77 cm long by 1 cm diameter bore) was designed and built for testing insulator materials. The firing parameters were held fixed and the rail to rail resistance of various insulators was measured versus shot number. The insulators studied include a variety of glass filled polymers, and filled and unfilled thermoplastics. Insulator, projectile, and rail mass losses were also measured. A voltage polarity dependence of the rail mass loss was clearly demonstrated. The surface conduction of the insulators was measured as a function of distance from the breech. The tests indicate that a significant improvement in performance over filled epoxy materials is possible with certain polymers.