Abstract: A positive characteristic thermistor, in which the outer periphery of a first electrode including a metal other than silver as its main component is positioned on the inside of the outer periphery of the main body of this thermistor, and is made to coincide with the outer periphery of a second electrode which includes silver as its main component and formed on the first electrode or to be placed on the inside of the periphery of the second electrode.

Abstract: A method of making a positive temperature coefficient of resistance (PTCR) device,and the PTCR device itself, where there is provided a ferroelectric semiconductor having a Curie point and a bulk resistance. A layer of electrically conducting material is provided upon the ferroelectric semiconductor. The layer is heated at a process temperature greater than the Curie point of the ferroelectric semiconductor for a period of time. End cooled to ambient temperature. The process temperature and time period are selected to be sufficient to provide an ambient layer resistance greater than the bulk resistance of the ferroelectric semiconductor. The layer may be heated in an oxidizing atmosphere or in a reducing atmosphere which also affects the layer resistance. The ferroelectric semiconductor may be in the form of an oxide ceramic or liquid crystals, and may include barium titanate. The layer may be selected from the group consisting of metal, metal alloys, metal oxides, polymers, and composites thereof.

Abstract: A PTC element displaying low volume resistivity and excellent PTC characteristics contains conductive carbonaceous particles having a large particle size, small specific surface area and being essentially unstructured such particles being, for example, thermal black or mesocarbon microparticles. The conductive particles are heat treated in an inactive atmosphere, blended with a crystalline polymer and then cross-linked by gamma radiation. In a variant form, the polymer can be chemically grafted onto the particles. The very low resistivity and excellent PTC characteristics of this PTC device make it suitable for miniaturization.

Abstract: A self-recovery PTC device for overcurrent protection of electrical circuits is made with a polymer/metal powder composition electrode that displays stable resistivity over a broad range of contact forces. Secure bonding of electrodes to a PTC element is achieved because both components are polymer composites, eliminating the problems associated with attempts to bond metal electrodes to a polymer PTC element. Swelling of metal electrodes, that results from outgassing by a PTC element, is also eliminated, because polymer electrodes are gas permeable.

Abstract: A thermistor element in which in a thermistor body having first and second outer electrodes formed on a pair of its end surfaces, a first inner electrode connected to the first outer electrode and a second inner electrode connected to the second outer electrode are so disposed that their ends are opposed a predetermined distance away from each other.

Abstract: A thin-film thermistor element which has an electrically insulating substrate having first and second surfaces opposite to each other and also having a pair of through-holes defined therein so as to extend completely across the thickness thereof, and a pair of electrode films each including a body portion of large surface area and a generally comb-shaped portion continued outwardly from the body portion. The electrode films are formed by the use of a firing process on the first surface of the substrate with the respective comb-shaped portions thereof confronting with each other. First and second electroconductive films are also formed on respective surrounding wall faces defining the corresponding through-holes in the substrate in electrically connected relationship with the body portions of the associated electrode films. A temperature sensitive resistance film is formed by the use of a high frequency sputtering process on the first surface of the substrate so as to overlay the electrode films.

Abstract: A polymer thick film ink which exhibits PTC behavior comprising an organic polymer which is crystalline, an active solvent suitable for dissolving the polymer, and carbon black which has a pH of less than 4.0. The ink is particularly useful in producing electrical devices such as heaters and circuit protection devices.

Abstract: A device capable of accurate temperature measurement down to 0.01.degree. K. of an object whose temperature is to be measured consisting of a heat sink wafer a first conducting pad bonded near one end of the heat sink wafer and a second conducting pad bonded near the other end of the heat sink wafer, an oblong doped semiconductor crystal such as germanium, the oblong doped semiconductor crystal has a third conducting pad bonded on its top surface and a fourth conducting pad bonded on its bottom surface with the oblong doped semiconductor crystal bonded to the heat sink wafer by having the fourth conducting pad bonded to the first conducting pad, a wire bonded between the second and third conducting pads, and current and voltage applying wires bonded to the first and second conducting pads whereby the change in resistance of the oblong doped semiconductor crystal indicates the temperature of an object whose temperature is to be measured.

Abstract: A diamond thermistor is described. Surface portions of temperature sensing diamond of the thermistor are doped with impurity ions by ion implantation except for a sensing area thereof. A pair of electrodes are formed on the impurity regions in order to make good ohmic contacts with the diamond. The damage caused by the ion implantation is remedied by subjecting the diamond film to laser annealing.

Abstract: A diamond thin film thermistor having a substrate, an electrically insulating diamond layer formed on the substrate by vapor-phase synthesis, a semiconducting diamond layer as a temperature-sensing part on the electrically insulating diamond layer by vapor-phase synthesis, and metal thin film electrodes attached to the semiconducting diamond layer. A plurality of such diamond thin film thermistors can simultaneously be formed on a single substrate, and the substrate is cut with a dicing saw to provide individual diamond thin film thermistor chips of the same quality.

Abstract: Self-regulating articles, particularly heaters, containing two spaced-apart elongate electrodes which are joined together by a melt-extruded element composed of a conductive polymer. The conductive polymer is a dispersion of carbon black in a crystalline polymer, has a resistivity at room temperature of R ohm-cm, and contains L % by weight of carbon black, L being not greater than about 15, and L and R being such that2L+5 log.sub.10 R.ltoreq.45.

Abstract: A silicon-based sensor includes a substrate, a sensor element, and a protective diaphragm mounting and covering the sensor element. The diaphragm is a silicon layer which, in a preferred embodiment, includes an etch-stop dopant. The etch-stop layer is sealed to the substrate so that the layer covers and mounts the sensor element to the substrate. The sensor is fabricated by forming a trough area in a surface of a silicon block (e.g., a silicon chip or wafer), treating the trough area with an etch-stop dopant (e.g., boron), depositing a sensor element onto the doped trough area, sealing at least the periphery of the doped trough area to a surface of a substrate (e.g., glass) so as to encapsulate the sensor element, and then etching away undoped regions of the silicon block so that the doped trough area remains as a protective diaphragm sealed to the substrate and covering the sensor element. It is also possible to form a bonding pad on untreated (e.g.

Abstract: MnO.sub.2-x thin films (12) exhibit irreversible memory switching (28) with an "OFF/ON" resistance ratio of at least about 10.sup.3 and the tailorability of "ON" state (20) resistance. Such films are potentially extremely useful as a "connection" element in a variety of microelectronic circuits and arrays (24). Such films provide a pre-tailored, finite, non-volatile resistive element at a desired place in an electric circuit, which can be electrically turned OFF (22) or "disconnected" as desired, by application of an electrical pulse. Microswitch structures (10) constitute the thin film element, contacted by a pair of separate electrodes (16a, 16b) and have a finite, pre-selected ON resistance which is ideally suited, for example, as a programmable binary synaptic connection for electronic implementation of neural network architectures. The MnO.sub.

Abstract: A process for preparing an electrical device which has a conductive polymer exhibiting PTC behavior. The cross-linking may be to a level of 50 to 100 Mrad or higher for devices designed to withstand high voltage test conditions. The device may be a laminar device having a center layer of higher resistivity than two surrounding layers.

Abstract: A self-regulating heating element (1) comprising a crosslinked copolymer based on ethylene and a comonomer of vinyl acetate in which the proportion of vinyl acetate is less than 10% and more than 2% by weight, more especially from 9 to 2% by weight and, in practice, from 9 to 5% by weight, said copolymer containing from 13 to 30% by weight carbon black and having a ratio ##EQU1## of greater than 10.sup.4.

Abstract: An electrical heater which has a conductive polymer resistive element and two laminar electrodes. The electrodes are shaped and positioned such that there is a continuous margin around the periphery of the resistive element on at least one surface. The margin is particularly useful in reducing arcing which may occur between the electrodes.

Abstract: A PTC polymer assembly in which a sheet of PTC polymer is sandwiched between two electrodes, and electric terminations are mechanically and electrically connected to the electrodes, at least one of the terminations is a looped spring connected at one end to one of the electrodes and at another end to a mounting element, with a loop between the electrode and the mounting element to which it is mechanically connected.

Abstract: An integrated sensing device includes a resistance temperature sensor formed in a semiconductor substrate and a resistance heater which is formed on an insulating layer which covers the surface of the semiconductor substrate. The resistance heater has a low temperature coefficient of resistivity and is positioned adjacent the resistance temperature sensor so the current flow through the resistance heater will generate heat which is transferred through the insulating layer to the resistance temperature sensor. The sensing device is applicable to a variety of sensing systems, such as mass flow measurement systems, dew point detection systems, and frost detection systems.

Abstract: A thermistor comprising a substrate and a heat sensitive element consisting of a semiconductive thin film diamond, which can measure high temperatures up to 800.degree. C. or higher.

Abstract: A low liquid level sensor fabricated on a silicon substrate having four temperature dependent elements formed thereon in a Wheatstone Bridge configuration. A thin, wire-like extension of the substrate between two openings within the substrate provides a mounting member for the fourth element. The other three elements are spacially separated from the fourth element such that the fourth element becomes exposed to air during a low liquid level condition while the other three elements remain submerged within the liquid. Accordingly, the Wheatstone bridge configuration and relative positioning of the elements on the substrate eliminates the need for corrections due to temperature variations and power supply fluctuations.

Abstract: A temperature detector having a semiconductor layer which is a p-type or n-type semiconductor doped by addition of an impurity. The semi- semiconductor is completely amorphous, or substantially amorphous with the inclusion of microcrystals. The temperature detector has good sensitivity at a temperature of not more than 100 K, and has good linearity of the change of resistivity to the change of temperature over a wide range of temperature.

Abstract: A thermistor element having a positive temperature-resistance coefficient. Electrodes are connected to the positive characteristic thermistor element, around which an outer member of an armor material is formed. The armor material is composed of a synthetic resin, in which 60-80 wt. % of an insulating filler consisting of, for example, silica, alumina or the like is mixed.

Abstract: Electrical devices containing PTC conductive polymers which have been cross-linked in two steps, preferably by radiation. The conductive polymer is heat-treated above the temperature at which it begins to melt between the two cross-linking steps, and/or the cross-linking steps are such that a center section of the conductive polymer, intermediate the electrodes, is substantially more cross-linked than the conductive polymer adjacent the electrodes. The process is particularly useful for the preparation of circuit protection devices which are subject to high voltage faults.

Abstract: A thermistor element for temperature measurement has a thermistor chip in wafer form and thin film electrodes formed on respective principal surfaces of the thermistor chip. The thin film electrodes are formed by evaporation. Lead wires are adhered to the thin film electrodes with heat-resisting conductive material. The assembled members are sealed with glass. The electrodes may be made of two-layer films.

Abstract: A thermal protector using a polymeric PTC element, with broad upper and lower surfaces, sandwiched between and held in intimate mechanical and electrical contact over substantially its entire broad surfaces with inner broad surfaces of upper and lower plate-terminals. Electrical insulation between the upper and lower plate-terminals outside the areas of contact of the plate-terminals and the PTC element electrically insulates the upper and lower plate-terminals from one another. The plate-terminals are clamped mechanically, preferably in such a way that the PTC element is biased continuously against the broad surfaces of the plate-terminals.

Abstract: An electrical resistor having a negative temperature coefficient for incremental resistance values has a resistance wafer with solderable coatings on opposite sides thereof and current lead elements soldered to the coatings, with the soldered ends of the lead elements being each coiled to form an annular eye, the soldering covering only the region of the eye and leaving the remainder of the coatings outside of the eye free of solder.

Abstract: Subject-matter of this invention is a thermistor-bolometer comprising as a detector body a structure consisting of a low resistivity layer of a doped magnetic garnet, two contact elements of conductive material adapted to form ohmic contacts and two conductive wires connected with the contact elements by contact pads, in order to connect the detector body with the biasing circuit and with the read-out circuit.

Abstract: A positive temperature coefficient (PTC) device, preventing silver migration effect and partial excessive heating, comprises a circular semiconductor PTC ceramic plate having a pair of first non-silver conductive layers attached on both surfaces of said PTC ceramics plate. A pair of second conductive layers, including silver, is attached on the first layers and an elongated periphery portion on the first layers is left without said second layers. A pair of conductive terminals couples the PTC element with an external circuit, each terminal having a convex portion to contact and support the PTC plate at the second layers so that the first layers do not directly touch with the terminals.

Abstract: Novel acrylonitrile butadiene and carboxylated acrylonitrile butadiene elastomeric admixtures compounded with various amounts of mineral fillers such as silicates, silicas, etc., carbon blacks, and plasticizers such as esters, epoxidized polyesters, etc., are useful as continuous temperature-sensitive solids when applied to metallic conductors as coatings whereby one leg acts as a conductor and the other is used as the sensing leg. These electrical properties of these admixtures such as volume resistivity, impedance, and reactance are uniquely sensitive to temperature changes from room temperature to at least 90.degree. C. and thus offer new and important circuit design opportunities for monitoring and detecting temperature changes. These admixtures which are essentially thermosetting may be combined with other resins such as polyvinyl chloride and used thermoplastically. In these cases, the elastomer becomes the plasticizer.

Abstract: A thin film resistor for use in microelectronic devices, the resistor having a resistive layer comprising silicon nitride (Si.sub.3 N.sub.4) and refractory metals of tungsten and/or molybdenum. The features of the structure of the resistor is that the film comprises a silicon nitride layer and grains of metal and/or metal silicide, wherein the resistivity is determined mainly by the silicon nitride. Therefore, the total resistance of the resistor can be controlled by controlling the amount of the silicon nitride, thus providing a wide range of the resistivity of 10.sup.-3 to 10.sup.9 .OMEGA.cm. Other characteristics such as immunity to the dopant contained in an adjacent doped layer, namely heat resistivity and low activation energy of the resistivity are verified by associated experiments.

Abstract: A flexible heating wire includes a first conductive body, a second conductive body, a thermally fusible electrically insulative body which are arranged such that the first and second conductive bodies will be brought into electric contact with each other when the thermally fusible electrically insulative body is thermally fused, a third conductive body, and a heating body having a positive temperature coefficient and held in electric contact with at least one of the first and second conductive bodies and the third conductive body. The flexible heating wire is capable of self-controlling the temperature of the heated heating body. The flexible heating wire can detect the danger of localized overheating, abnormal overheating, or the generation of an arc which is caused when the heating wire is subjected to external oppression, bending, or twisting, or when the heating wire is heated by an external source, or when a conductive material has been mixed in the PTC heating body.

Abstract: An electrically heat-recoverable assembly comprising a heat-recoverable article and a pair of electrodes. The electrodes supply current to the article without interferring or limiting the way in which the article can be deformed in order to render it heat recoverable. The electrodes are placed and connected to the article in light of the properties of the article, especially its volume resistivity. The assembly significantly reduces the possibilities of arching or sparking while generating sufficient heat that is generated sufficiently uniformly throughout the article.

Abstract: Improved liquid helium level gauge is described. The gauge includes a resistance wire sustained vertically within a liquid helium container and an electrical indicating device for producing an indication which varies with the electric resistance of said resistance wire. The resistance wire is made of a new superconductive amorphous material such as Zr.sub.80 Nb.sub.5 Al.sub.8 Si.sub.7. The amorphous material has a superconductivity transition temperature between 4.2.degree. and 5.0.degree. K., a relatively high normal electric resistance and a high mechanical strength.

Abstract: Method and apparatus for producing an electrical conductor are provided comprising a doped polymeric material and an encasement means substantially impermeable to the dopant, the encasement means having matching surfaces in contact with the polymeric material to reduce the loss of dopant and an inert gas to occupy any voids between the surfaces.

Abstract: A heating device for heating an object with a heating element composed of ceramic particles having a positive temperature coefficient of resistance dispersed in a binder.

Abstract: A heating element comprises a resistor comprising a plurality of fine particles or thin films having a negative temperature coefficient of electrical resistance, and highly resistant region layers interposed between the fine particles or thin films, at least two separate electrodes arranged in contact with different particles or layers of the resistor, and means for applying across said electrodes an AC electric voltage, said means operable at AC frequencies which are not lower than a frequency whose complex impedance characteristics which when graphed in the manner shown in FIG. 4 hereof correspond to point B of said graphed complex impedance characteristics. This heating element has the following merits that it can be formed into an optional shape, is low in the power consumption, can be rapidly heated, has temperature self-adjusting performance and temperature detecting performance and is excellent in the durability.

Abstract: An electrically symmetrical temperature sensor includes two highly doped zones which are formed in a semiconductor body of one conductivity type, which are provided with connection contacts, and have the same conductivity type as that of the body. A temperature-dependent resistor is formed between the two highly doped zones. In order to avoid mechanical strains due to the temperature differences which occur during operation and which invalidate the resistance value, and in order to be able to incorporate the semiconductor body without great difficulty in simply-constructed envelopes, in particular in glass envelopes of the type frequently used for rectifier diodes, the zones of the same conductivity type are located opposite each other on opposite sides of the semiconductor body. Further, the semiconductor body comprises neutron- transmuted n-type silicon.

Abstract: A planar heating element having a positive temperature coefficient has a plurality of spaced electric current supply lines constituted by contact bands and a planar support, the electric current supply lines being operatively connected to the planar support, the contact bands and the support including an electrically conductive synthetic resin whose electrical resistance has a positive temperature coefficient.

Abstract: Conductive polymer compositions which exhibit PTC behavior and comprise carbon black (or other particulate conductive filler) dispersed in a cross-linked polymer component comprising a cycloolefin polymer having a crystallinity of at least 5% and a melting point in the range 0.degree. to 80.degree. C. These compositions are particularly useful in the form of heaters which self regulate at a temperature in the range of 0.degree. to 70.degree. C. Such heaters are particularly useful for freeze protection and for heating human and other animal bodies.

Abstract: Electric resistor, including a PTC body being formed of ceramic material and having opposite poles, two opposite outer side surfaces being parallel to the longitudinal axis of the PTC body and two opposite end faces perpendicular to the outer side surfaces, the PTC body having rows of mutually parallel depressions formed in the end faces defining inner surfaces and leaving partitions therebetween, metal coatings disposed on the inner surfaces at the opposite poles and partitions, metal layers disposed on the outer side surfaces, and metal strips being disposed on the end faces interleaved in comb-fashion and being connected to the metal layers, defining current flow paths from the metal layers and metal strips through the partitions being perpendicular to the longitudinal axes of the depressions and electrically connecting the pole coatings of a respective row of depressions to each other, and a method for the manufacture thereof.

Abstract: A thermistor using an organophosphazene polymer having aryloxyl and/or alkoxyl group pendants as a thermo-responsive material. The organophosphazene polymer has an excellent responsiveness to temperature change, and can be molded into desired forms. The thermistor having good reliability and good heat and flame resistances can be prepared with good processability and in good yield.

Abstract: A rectangular wafer thermistor comprises a piece of ceramic thermistor material having electric contact material covering its opposite surfaces. A contact defining score mark with an open geometric shape other than a straight line extends across the thermistor through one layer of the contact material for separating the contact material on that surface into two contacts. The ends of the contact defining score mark intersect the opposite edges of the thermistor at different locations along the thermistor. The contact defining score marks may be V or U or otherwise shaped, and the intersections between the different sections of these score marks are preferably rounded, but may be sharp corners. The shape of the contact defining score mark prevents the thermistor from breaking at the contact defining score mark when the thermistor is broken off a large sheet of thermistor material.

Abstract: Polymers having low surface energy, e.g. fluorocarbon polymers, are rendered printable by conventional methods, e.g. offset printing, by incorporating a suitable particulate filler in the polymer, and shaping the filled polymer under conditions which result in the surface of the shaped polymer having irregularities which correspond to the particles of the filler. Suitable fillers comprise particles having at least two dimensions in the range of 1 to 40 microns; glass fibers are particularly satisfactory. Extruded insulating polymeric jackets for electrical components, e.g. strip heaters and wire and cable, can readily be marked by use of the invention.

Abstract: A functional electric device is described, which device comprises a functional material layer, and a pair of electrodes separated from each other and electrically contacting with the functional material layer. At least one of the pair of electrodes is made of copper or an alloy of copper and a copper inactivating agent is present between the functional material layer and the at least one of the paired electrodes. The functional electric device includes heat-sensitive, fusing and photovoltaic elements.

Abstract: A platinum thin film is formed by sputtering platinum onto an insulating substrate and heat aging the platinum thin film in a stairstep manner. A kerf is formed in the platinum thin film to produce a desired resistance, and a metal oxide semiconductor film is thereafter deposited on the platinum thin film to produce a gas sensor.

Abstract: A self-regulating electric heater includes a casing made of ceramic and a heating unit housed in the casing. The heating unit includes a PTC body for generating heat when electric current is supplied, heat dissipating plates essentially made of brass and coupled to the PTC body in such a manner as to sandwich the PTC body between the heat dissipating plates and terminals connected to each of the heat dissipating plates for the external electrical connection. The self-regulating electric heater further includes lid member and sealing member for sealing the casing hermetically.

Abstract: Conductive polymer compositions which have improved voltage stability and which preferably exhibit PTC behavior. The compositions comprise a carbon black dispersed in a crystalline copolymer of an olefin and at least 10% by weight of an olefinically unsaturated comonomer containing a polar group. The carbon black has a particle size greater than 18 millimicrons, preferably greater than 30 millimicrons, a d-spacing greater than 360 and a surface area which is less than1.2S+e.sup.S/50where S is the DBP absorption of the carbon black. The carbon black is preferably present in amount at least 15% by weight of the composition. Particularly useful devices including such compositions are self-regulating heaters.

Abstract: A semiconductor integrated circuit supporter on which a heating element is dielectrically provided, said supporter comprising a package, printed circuit board, mother board, etc. for supporting a semiconductor integrated circuit which includes devices such as transistors.The heating element provided on said semiconductor integrated circuit supporter is capable of heating the whole or a required part only thereof so that the semiconductor integrated circuit is preheated to a temperature required for its normal operation with precision and stability thereby improving the accuracy and reliability of various devices of which a semiconductor integrated circuit is composed as well as the control by said devices.

Abstract: A semiconductor strain gauge transducer comprising a sensitive element which is a monocrystal sapphire substrate carrying epitaxial silicon strain gauges of p-type conduction. The hole concentration in the silicon is 3.5.multidot.10.sup.19 to 3.multidot.10.sup.20 cm.sup.-3. The silicon strain gauges are interconnected to form a bridge or differential strain-sensitive circuit.

Abstract: A method for making a carbide thin film thermistor which comprises providing an insulating substrate, forming at least one pair of electroconductive electrodes on the substrate in a desired pattern, and forming a carbide resistor film on the insulating substrate and the electroconductive electrodes by sputtering process while leaving part of the electrodes exposed for external connections. A carbide target material is sputtered in an inert gas atmosphere containing a small amount of an impurity gas. The thermistor element is arbitrarily controlled to have a desired level of resistance by choice of the impurity gas, the amount of such gas and the mode of sputtering. Optionally, the element is trimmed to adjust its resistance accurately and is also hermetically sealed within a glass tube to prevent the element from being contaminated with harmful substances.