Abstract: An integrated-circuit one-way isolation-coupler for a controlling electrical circuit and a controlled electrical circuit and improvements in carrier-domain magnetometers and other applications thereof. In the isolator a magnetic-field source, such as a flat coil, produces a magnetic field from current applied from the controlling circuit, while a detector such as a carrier-domain-magnetometer detects the magnetic field so produced and produces a signal therefrom. A dielectric medium, such as silicon dioxide or silicon nitride separates the source from the detector. The source, the detector, and the dielectric medium, are all incorporated on a single IC chip, such as silicon, or gallium arsenide, or semiconductor material. An amplifier may also be incorporated and may deliver the amplified signal to the controlled circuit. Preferably there are two carrier-domain-magnetometers located so that they are symmetrical with respect to the flat coil.

Abstract: A miniature diaphragm pressure transducer. A thin diaphragm of silicon nitride has an upper face covered by a zinc-oxide piezoelectric film encapsulated in chemical vapor deposited silicon dioxide. A series of annular, basically conentric, polysilicon electrodes are provided in the silicon dioxide between the piezoelectric film and the diaphragm and in contact with the piezoelectric film. A series of annular, basically concentric, aluminum electrodes are on the opposite side of the piezoelectric film from the polysilicon electrodes and are aligned with the polysilicon electrodes; they lie over the silicon dioxide, and are in contact with the piezoelectric film.

Abstract: An integrated-circuit one-way isolation-coupler for a controlling electrical circuit and a controlled electrical circuit and improvements in carrier-domain magnetometers and other applications thereof. In the isolator a magnetic-field source, such as a flat coil, produces a magnetic field from current applied from the controlling circuit, while a detector such as a carrier-domain-magnetometer detects the magnetic field so produced and produces a signal therefrom. A dielectric medium, such as silicon dioxide or silicon nitride separates the source from the detector. The source, the detector, and the dielectric medium, are all incorporated on a single IC chip, such as silicon, or gallium arsenide, or semi-conductor material. An amplifier may also be incorporated and may deliver the amplified signal to the controlled circuit. Preferably there are two carrier domain-magnetometers located so that they are symmetrical with respect to the flat coil.

Abstract: A miniature diaphragm pressure transducer. A thin diaphragm of silicon nitride has an upper face covered by a zinc-oxide piezoelectric film encapsulated in chemical vapor deposited silicon dioxide. A series of annular, basically concentric, polysilicon electrodes are provided in the silicon dioxide between the piezoelectric film and the diaphragm and in contact with the piezoelectric film. A series of annular, basically concentric, aluminum electrodes are on the opposite side of the piezoelectric film from the polysilicon electrodes and are aligned with the polysilicon electrodes; they lie over the silicon dioxide, and are in contact with the piezoelectric film.

Abstract: A method and the product resulting from the method, for making a microminiature structure with two or more members measuring less than 1000 micrometers in any linear dimension and relatively movable to each other, comprising the steps of (a) providing a first sacrificial coating over a substrate having openings therethrough to expose a portion of the substrate, (b) depositing a first structural layer over the first sacrificial coating and the exposed portion of the substrate, with openings therethrough to expose a second portion of the substrate, (c) providing a second sacrificial coating over the second exposed portion of the substrate and said first structural layer, with openings through both the first and second sacrificial layers to expose a third portion of the substrate, (d) adding a second structural layer thereover and defining it, (e) possibly adding alternately other sacrificial coatings and other structural layers, and (f) etching the first and second and other sacrificial layers to remove them co

Abstract: A polysilicon microstructure is formed on a silicon substrate. Beneath the microstructure, are diffused regions in the substrate. The microstructure is capacitively coupled to these diffused regions so that one such capacitor acts as an excitation capacitor and the other capacitor acts as a sense capacitor. By applying an AC voltage to the excitation capacitor, the electrostatic force between the substrate and the microstructure changes causing a mechanical vibration in the microstructure. A DC voltage is applied to the sense capacitor. The mechanical vibration, which changes its capacitance, will develop a current through the sense capacitor. A phenomenon may then be sensed by the vibrating microstructure. A polymer film disposed on the microstructure can sorb a gas of interest. As the mass of the polymer film and vibrating microstructure increases, its frequency or phase changes. The current through the sense capacitor will exhibit a commensurate frequency or phase shift.

Abstract: A mobile fluid purification unit comprises a plurality of treatment tanks mounted on a skid and interconnected by hoses for series flow, parallel flow or a combination of series and parallel flow for carrying out a variety of treatments of the liquid. A plurality of such mobile units can be mounted on a larger vehicle and connected to one another by one or several hoses to provide greater capacity and variety than is possible in a single mobile unit. A cover which may include a heater can be provided for the unit or units.

Abstract: An integrated circuit pyroelectric sensor includes two MOSFETS coupled in a differential amplifier configuration, each MOSFET having a common source. A pyroelectric capacitor is coupled to the gate of a respective one of the MOSFET. A polysilicon filament is disposed between the pyroelectric capacitors which acts as a heating element when a current is passed therethrough. The voltage difference between the drain of each MOSFET is thus a function of the voltage difference between the pyroelectric capacitors. One of the pyroelectric capacitors is disposed at the leading edge of the sensor with respect to the direction of a fluid flow. The fluid flow across the sensor will cause the first capacitor to have a different temperature than the other capacitor of the trailing edge of the sensor whose temperature is a function of the temperature of the heating element.

Abstract: A mobile system for purifying liquids, such as water, including a truck trailer in which multiple purification treatment tanks are mounted. The system includes an inlet, an outlet, conductivity measuring equipment for monitoring the quality of the purified liquid, and specially designed liquid conduits and valves which permit the treatment tanks to be operated in series, in parallel, or in series/parallel. The treatment tanks can be filled with any desired purification material. The trailer is enclosed and heated to protect the system from cold temperatures.

Abstract: This disclosure relates to a method and apparatus for sensing the presence of gases, vapors, and liquids using surface acoustic waves. At the present time the commercially available devices for measuring the presence of fluids, although fast reacting and generally quite accurate, are very expensive and bulky. Further, these devices do not lend themselves to advanced integrated signal processing and digital techniques. This disclosure describes a precise, fluid sensing unit that is small, easily integrated, and relatively inexpensive to fabricate. The apparatus includes a medium on which surface acoustic waves can be propagated, transmitting and receiving transducers, and a sensing member located across the path of the surface acoustic waves. The sensing member has a physical characteristic that varies the velocity and/or the attenuation of the waves when in the presence of the specific fluid being detected.

Abstract: An integrated circuit and method for forming the same including a lateral bipolar transistor having an increased current gain. Floating islands are formed in the emitter of the lateral transistor to have a conductivity type opposite that of the emitter and which act to channel current towards the periphery of the emitter, thereby directing the current towards the collector region. In addition, the integrated circuit includes a buried layer underlying the lateral transistor with the buried layer pinched very thin along a region which outlines the edge of the emitter for enhancing lateral current flow.

Abstract: A high speed threshold switching integrated circuit including a transistor and an integrally formed tunnel diode connected in parallel between the base and emitter of the transistor. The heavy doping necessary for the tunnel diode is achieved through the use of ion implantation. A current pulse applied to the emitter-base contact of the integrated circuit causes no collector current to flow until the point at which the rising current pulse exceeds the peak current of the tunnel diode. As the tunnel diode goes into the negative resistance region the transistor is turned on and rapidly pushed into near saturation with a consequent rapidly rising collector current.