Showing papers on "Insulator (electricity) published in 1987"

Semiconductor device and process for producing the same

Abstract: A semiconductor device having improved heat-dissipating characteristics employs a thin insulator film made of diamond, which has excellent thermal conductivity, as an insulator film which is formed on a chip immediately below a heat-dissipating bump electrode. Since the thin diamond film has excellent insulating properties and high thermal conductivity, it is possible to improve heat-dissipating characteristics of even a high-power semiconductor device such as a multichip module. In the case of, particularly, a multichip module, the insulation between a mother chip and a child chip can also be ensured by the presence of the thin diamond film.

Optimizing Field Stress on 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 among 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.

Manufacture of thin-film transistor

Abstract: PURPOSE: To improve a thin film transistor remarkably in an electrical property and stability by a method wherein a gate insulator layer is formed in such a process that insulator, or metal or semiconductor constituting insulator is sputtered by an ion beam as the surface of a substrate on which the gate insulator layer is to be formed is irradiated by ultraviolet rays and spouted by gas. CONSTITUTION: A first gate insulator film 3 is formed in such a manner that a beam of Ar + , O + , or mixed these ions is irradiated from an ion beam device 21 onto a sputtering target 2, for example, under such a condition that a beam voltage is 500V and a beam current is 200mA so as to sputter Al or Al oxide from the sputtering target 2. Moreover, the face of a substrate 1 is irradiated and spouted by ultraviolet rays and oxygen gas respectively through an ultraviolet ray source and an oxygen outlet 23. In this process, oxygen can be activated in reaction by irradiating ultraviolet rays whose wavelength is 130nm∼300nm. By these processes, as oxygen is sufficiently supplied, the insulator film 3 whose composition is close to a stoichiometric composition can be obtained, which is dense and very small in oxygen deficiency inside the film. COPYRIGHT: (C)1989,JPO&Japio

Solid-state non-volatile electronically programmable reversible variable resistance device

Abstract: A solid-state variable resistance device (10) whose resistance can be repeatedly altered by a control signal over a wide range, and which will remain stable after the signal is removed, is formed on an insulated layer (14), supported on a substrate (12) and comprises a set of electrodes (16a, 16b) connected by a layer (18) of material, which changes from an insulator to a conductor upon the injection of ions, covered by a layer (22) of material with insulating properties which permit the passage of ions, overlaid by an ion donor material (20). The ion donor material is overlaid by an insulating layer (24) upon which is deposited a control gate (26) located above the contacts. In a preferred embodiment, the variable resistance material comprises WO 3 , the ion donor layer comprises Cr 2 O 3 , and the layers sandwiching the ion donor layer comprise silicon monoxide. When a voltage is applied to the gate, the resistance between the electrode contacts changes, decreasing with positive voltage and increasing with negative voltage.

Total Dose Hardening of Buried Insulator in Implanted Silicon-on-Insulator Structures

Abstract: Total dose characteristics of the buried insulator in implanted silicon-on-insulator (SOI) substrates have been studied using MOS transistors. The threshold voltage shift of the parasitic back channel transistor, which is controlled by charge trapping in the buried insulator, is reduced by lowering the oxygen dose as well as by an additional nitrogen implant, without degrading the front channel transistor characteristics. The improvements in the radiation characteristics of the buried insulator are attributed to the decrease in the buried oxide thickness or to the presence of the interfacial oxynitride layer formed by the oxygen and nitrogen implants.

Low-voltage field emission from tungsten fiber arrays in a stabilized zirconia matrix

Abstract: Field emitter array cathodes were fabricated from unidirectionally solidified composites of tungsten fibers in an insulating yttria-stabilized-zirconia (YSZ) matrix. A close-spaced molybdenum gate film (extractor) was formed utilizing e-beam evaporation of alumina as an insulator, which was overlayed by the molybdenum extractor. The high resistivity of the composite matrix coupled with the alumina insulator resulted in low leakage current and permitted dc operation of the device. Emission testing demonstrated current densities of 1--5 A/cm/sup 2/ with leakage in the ..mu..A range for applied potentials of 125--200 V. Variation of emitter tip geometries from hemispheres to right circular cylinders to pointed cones produced increases in emission consistent with reduced tip radii.

Shielded cable assembly comprising means capable of effectively reducing undesirable radiation of a signal transmitted through the assembly

Abstract: For reducing undesirable radiation of a signal, a shield cable assembly includes a cylindrical magnetic member fitted around a shielded-conductor cable to which a shielded joint is electrically and mechanically connected. An inner insulator is mounted in a connecting portion between the cable and the joint so as to support electrical contacts of the joint together with extened portions of insulated conductors of the cable, in electrical connection with one another. An electrical conductive coating is applied on the surface of the inner insulator, and is electrically connected to a cable shield of the cable. As a result, the magnetic member and the coating cooperate to reduce undesired radiation of signals from the assembly. In addition, an outer insulator encloses the inner insulator and the magnetic member, thus to connect mechanically the inner insulator with the magnetic member.

Linear particle accelerator with seal structure between electrodes and insulators

Abstract: An electrostatic linear accelerator includes an electrode stack comprised of primary electrodes formed or Kovar and supported by annular glass insulators having the same thermal expansion rate as the electrodes. Each glass insulator is provided with a pair of fused-in Kovar ring inserts which are bonded to the electrodes. Each electrode is designed to define a concavo-convex particle trap so that secondary charged particles generated within the accelerated beam area cannot reach the inner surface of an insulator. Each insulator has a generated inner surface profile which is so configured that the electrical field at this surface contains no significant tangential component. A spark gap trigger assembly is provided, which energizes spark gaps protecting the electrodes affected by over voltage to prevent excessive energy dissipation in the electrode stack.

Shielded insulation for combustion chamber

Abstract: In an uncooled engine, it is propose to form insulator coatings on the combustion chamber surfaces, and to mechanically protect such coatings against erosion or cracking by means of outer protective layers applied over the insulator coatings. The insulator coatings can be zirconium oxide applied to a thickness of approximately 0.15 inch. The protective layers can be formed of various materials resistant to high temperatures in the vicinity of 2000° F., e.g. silicon nitride, steel or cast iron.

Novel Insulator Designs for Superior DC Hold-Off in Bridged Vacuum Gaps

Abstract: The dielectric strength of insulator-bridged vacuum gaps has been investigated under dc stresses. Contrary to many previous investigations, careful study undertaken here reveals that negative-angled conical frustrums withstand high er conditioned withstand voltages than positive frustrums and cylindrical insulators. The superior voltage perform ance of negative-angled conical frustrums over positive angled ones stems from negative charging of the former which supresses electron emission from the cathode triple junction X-ray emission within the bridged vacuum gap, and electron interaction with the insulator surface, due to emission from the cathode triple junction, are both shown to lower the voltage hold-off significantly. Novel insulator profiles were tested which exhibited significantly superior voltage hold-off over conventional cylinders and conical frustrums. The design strategy for such designs relied on: (1) providing stress relief at the cathode triple junction by facilitating the self-generation of negative charge on the insulator region near the critical junction, (2) minimizing X-ray production from the anode due to the impact of elec trons, and (3) minimizing electron interaction with the in sulator surface by moving the cathode triple junction away from the main body of the insulator.

Reduction of the concentration of slow insulator states in SiO2/InP metal–insulator semiconductor structures

Abstract: Spatially distributed states within the insulator are thought to be the origin of the well‐known drift phenomena usually found in InP metal–insulator semiconductor (MIS) devices. This paper will show that the concentration of these states can be reduced drastically by applying a suitable deposition technique. Plasma‐enhanced chemical vapor deposited SiO2 is used as the insulator in a process involving low substrate temperatures (200 °C), spatial separation of sample and plasma (indirect plasma method), and the addition of phosphorus into the reaction chamber during the initial stage of insulator deposition. The influence of several process parameters on the properties of the silicon dioxide films as well as the SiO2/InP interface characteristics are investigated. Deep level transient spectroscopy and C(V) measurements of InP MIS capacitors yield concentrations of slow insulator states of only 1–2×1011 cm−1 eV−1 for the best of our samples.

Optical waveguide arrangement for a high-voltage insulator

Abstract: In a high-voltage-conducting assembly (10), such as, for example, the current transducer arrangement for a high-voltage outdoor installation, measurement information items are transmitted via optical waveguides from high-voltage potential to ground potential. To reduce the voltage gradient along the optical waveguide, the latter is spirally conducted along an optical waveguide carrier (7) between the high-voltage side (9) and the ground potential side (5) of a high-voltage insulator (6). The optical waveguide support (7) can be a self-supporting plastic coil (7) or the outer layer of the insulator tube of fibre-glass-reinforced plastic of the high-voltage insulator (6) or its silicon layer applied on the outside or its silicon shield tape. In this arrangement, the surface leakage path of the optical waveguide support is greater than 1.5-times, preferably greater than 5-times the height (h) of the high-voltage insulator (6). The optical waveguide can be wound at a steep pitch onto the coil or arranged in a U-shaped groove of the coil or in the hollow space of a hose-spaced coil.

Reduction of the concentration of slow insulator states in SiO2/InP metal-insulator semiconductor structures

Abstract: Spatially distributed states within the insulator are thought to be the origin of the well‐known drift phenomena usually found in InP metal–insulator semiconductor (MIS) devices. This paper will show that the concentration of these states can be reduced drastically by applying a suitable deposition technique. Plasma‐enhanced chemical vapor deposited SiO2 is used as the insulator in a process involving low substrate temperatures (200 °C), spatial separation of sample and plasma (indirect plasma method), and the addition of phosphorus into the reaction chamber during the initial stage of insulator deposition. The influence of several process parameters on the properties of the silicon dioxide films as well as the SiO2/InP interface characteristics are investigated. Deep level transient spectroscopy and C(V) measurements of InP MIS capacitors yield concentrations of slow insulator states of only 1–2×1011 cm−1 eV−1 for the best of our samples.

Interpretation of capacitance-voltage characteristics of polycrystalline silicon thin-film transistors

Abstract: Measurements of the gate‐to‐channel capacitance in thin‐film transistors are potentially useful for rapid evaluation of insulator and interface quality. In this paper, we develop a transmission line model of the gate‐to‐channel capacitance. We then compare the model with measurements made on unpassivated polycrystalline silicon thin‐film transistors. An excellent fit to the measurements is obtained. Finally, we discuss the influence of semiconductor traps and insulator charge on the measured capacitance.

Particle-Initiated Breakdown Characteristics of Conical Insulator in N2 GAS and N2/02 Mixture under DC Voltage

Abstract: Particle-initiated breakdown characteristics of conical spacers were investigated experimentally in N2 and 79% N2/21% 02 gas mixture to provide fundamental parameters determining the breakdown voltage of a dielectric spacer contaminated by metallic particles. Experimental results show that the breakdown voltage of a particle-contaminated spacer increases with the value of |90-?|, while in contrary that of the clean spacer decreases with the value of |90-?| in the region of ? of 0|90-?|60 degrees where the spacer angle ? is defined as the angle between the spacer surface and the anode plane electrode. With a given spacer the breakdown voltage reveals the minimum value (MBDV) when a particle was placed very near the anode in N2/02 mixture, and on or very near the electrodes in N2 gas. At the particle conditions giving the MBDV, the corona stabilization effect is less effective. The MBDV decreases with decreasing in the gas pressure and the wire particle diameter. The critical particle length beyond which the breakdown voltage is lowered by the particle depends on the spacer shape. Analysis of the MBDV to include a minimum electric field necessary for discharge propagation along the spacer surface and the effect of the field enhancements due to particle on a cylindrical spacer shows fairly good agreement with the experimental results.

High voltage insulators

Abstract: A high performance, high voltage electrical insulator, for use at greater than 15 Kv in wet, contaminated conditions, is designed to give a minimum surface area while maintaining a low leakage current by specifying the ratios of shed diameter to shed pitch, leakage distance between support fittings to the straight line distance between support fittings, and the shed diameter to the support rod diameter. Through the use of specified silicone elastomeric compositions, or through the use of silicone compositions meeting specified electrical properties, an insulator meeting the design specifications is shown to be a useful high voltage insulator.

Heteroepitaxial selective-area growth through insulator windows

Abstract: Preferred embodiments include growth of GaAs on insulator-masked silicon; the GaAs is single crystal over the silicon but polycrystalline over the insulator. A post=growth anneal extends the single crystal region over the insulator for distances of 2-4 μm.

A new model for dielectric‐breakdown phenomenon in silicon dioxide films

Abstract: A new model is proposed to interpret the breakdown phenomenon of dielectric thin films such as SiO2 films over the whole range of an applied field. It is suggested that two main mechanisms are responsible for the dielectric breakdown which is influenced by the geomorphic and physical parameters, and the examination conditions. One of the mechanisms is the avalanche breakdown, the so‐called intrinsic type, which is caused by impact ionization. The other, the extrinsic type, is the filament‐heating transport which induces a destructive breakdown. A simple mathematical model invoking the role of photon absorption is constructed to describe the effects of the band gap and the insulator thickness on the dielectric breakdown. It can be deduced from the model that (i) the mean distance of impact ionization is equivalent to the minimum thickness of the film generating the impact ionization and (ii) the probability of impact ionization is a function of the width of the band gap of the insulator under an applied fi...

Spacer Involvement in Conducting-Particle-Initiated Breakdown in Compressed Gas Insulated Systems

Abstract: This paper describes the results of an investigation into conducting particle initiated breakdown in a 76/250 mm coaxial electrode configuration, representative of a 145 kV gas insulated transmission line (GITL) or gas insulated substation. A free moving particle is known to initiate breakdown through a sequential two-stage process. The involvement of an epoxy disk spacer in such a breakdown, when the particle is at a distance from the spacer, is studied through specially designed experiments. For 6.4 mm long, 0.45 mm diameter aluminum particles it is observed that the discharge path may involve the spacer surface even when the particle is several centimeters away from the spacer surface. However, the 60 Hz ac breakdown voltages for discharge paths involving the spacer surface are not significantly different from those without spacer involvement, if the particle-to-spacer distance is greater than 3 mm.

Compact device for long stroke energy absorption

Abstract: A compact device for absorbing kinetic energy generated by, for example, broken electric power lines on electric power transmission towers. The device consists of a non-spring helix, or in or out of plane flat coils that are placed between an electric transmission tower and the conductor insulator. The device deforms by plastically uncoiling in response to forces greater than a predetermined force. The device is a single-event device, designed to be replaced after one extraordinary dynamic event. The device can also be used in other structures or machinery requiring compact long stroke energy absorption.

Evidence of the role of defects near the injecting interface in determining SiO2 breakdown

Abstract: Experimental results on oxide breakdown in thin insulator metal‐oxide‐semiconductor structures are presented to show that at a microscopic level breakdown is related to defects located near the injecting interface. In addition, breakdown is found to be almost independent of electron fluence.

Manufacture of semiconductor carrier

Abstract: PURPOSE:To improve the productivity, by burying a semiconductor chip in a package consisting of side members provided by insulator frames and of an upper member provided by an insulation layer, and by connecting an electrode pad on the chip to input/output terminals of a carrier through a conductor pattern. CONSTITUTION:A semiconductor wafer 1 is cut off on a flexible support sheet 3 into separate chips 4. Insulator frames 5, which will be side members of a semiconductor carrier, are mounted in the gaps defined between the chips 4 so as to fill the gaps and to fix the chips positionally. An insulation layer 6, which will be a surface member, is then deposited on the chip. The insulation layer 6 is melt selectively above an electrode pad 4a on the chip 4 so as to provide an opening 7. Conductor patterns 8 are then formed on the surfaces of the insulator frames 5 and insulation layer 6 such that they are connected to the electrode pad 4a of the semiconductor chip through the opening 7 formed in the insulating layer 6. Finally, the insulator frame 5 is cut off between the semiconductor chips 4 so that semiconductor carriers 9 each consisting of one chip are obtained.

High-voltage insulator

Abstract: An insulator cap (12) is mounted purely by force-fitting/positive locking on the insulator body (4) of a high-voltage insulator (2) in order to produce a lock which is proof against being released. For this purpose, the insulator cap (12) is divided into preferably two symmetrical halves (18, 20) by means of at least one suitably located cut. The split insulator cap (12) can be placed over the conically expanding core (10) of the insulator body (4) and is fixed in position there by a retaining ring (26).

Insulator for an electrostatic particle precipitator, in particular soot precipitator for exhaust gases from diesel engines and method for operating the insulator

Abstract: Short-circuits may occur as a result of particles which accumulate on the surface of insulators. In order to avoid this it is already known to burn free a separating zone by means of an electric resistance heater (8) installed in the insulator. However, the disadvantage of this is that the insulator becomes conductive itself in the region of the heated zone, which can also lead to short-circuits. The new construction of the insulator serves to reliably avoid both types of short-circuits. For this purpose, the ... in the interior of the housing (3) is provided with a hollow annular space (9) which surrounds the electrode (5) and is closed off with respect to the interior of the housing (3) and the heating element (8) is attached to the outer wall of the annular space (9). The position of the heating element in the insulator permits short-circuit-free, discontinuous burning of precipitative soot.

Device including a temperature sensor

Abstract: A structure of alternating layers of titanium and an insulator or semiconductor material has temperature-sensitive electrical resistivity. In combination with a resistance-measuring circuit, such structure can serve as an accurate temperature sensor. And, since electrical resistivity is inversely related to temperature, disclosed structures can serve as miniature thermistors in integrated circuit devices.

Coaxial contact for termination to printed circuit boards and the like

Abstract: A coaxial contact for termination to printed circuit boards and the like includes an assembly featuring a dielectric insulator disposed within an outer contact. An outer tail is disposed within the outer contact and an inner tail is disposed within the insulator. The outer contact is staked to retain the outer tail within said contact, and to compress the insulator between the inner tail and the outer contact to retain the inner tail and the insulator within the assembly and to prevent leakage. Alternatively, adhesive joints may be used to retain the insulator within the outer assembly and the inner tail within the insulator.

Drilling method for printed wiring board

Abstract: PURPOSE:To accurately perform drilling of a printed wiring board, by adapting a pad plate to the printed wiring board, formed by laminating layers of conductor and insulator, through an adhesive layer and performing the drilling. CONSTITUTION:A printed wiring board 1 is formed, for instance, by a laminated structure piling three sheets of glass substrates impregnated with epoxy resin, and predetermined drilling is performed after piling a pad plate 3 on the observe of the printed wiring board 1 while a waste plate 5 on its reverse. The pad plate 3, which roughs a surface of aluminum foil, is adhesively attached to the surface of the printed wiring board 1 through an adhesive layer 2. The waste plate 5 is a base material of paper impregnated with phenol resin. High accurate drilling can be performed with no burr or return by drilling a fine hole by a drill from the upper of the pad plate 3.

Plasma cvd apparatus

Abstract: PURPOSE:To obtain the electrode structure of a P-CVD apparatus which can form a film of reproducible quality having uniform thickness distribution on an insulator substrate by covering the electrode surface of the side on which the substrate is mounted with an insulator having the same permittivity as that of the substrate CONSTITUTION:When a substrate 10 is set on an earth electrode 8, an earth cover electrode 9 and the electrode 8 are disposed in one plane in a structure, an electrode coating insulator 11 is clamped by screws at the periphery of the electrode, and the electrode 9 is floated over the substrate When growing an alpha-Si, an SiN film, a flake in a reaction chamber can be suppressed when the electrode is covered with an insulator such as a glass since the glass surface has larger bonding strength than the metal surface In other words, since the flake less occurs, the film can be continuously formed many times, and the probability that a problem such as a pinhole in the film occurs is lower than the conventional electrode structure To increase an electric field on the substrate, the thickness of the electrode coating insulator may be reduced, while to decrease the electric field, the thickness may be increased Accordingly, the thickness may be suitably set in response to the necessary film