Abstract: An electric conductive adhesive system includes a hydroxy terminated ether or ester thereof which serves as a conductivity enhancer. Conductivity levels attained exceed those of prior art systems.

Abstract: The specification describes techniques for coating fiber waveguides by passing the fiber through a reservoir of coating material while preventing the gross accumulation of bubbles in the reservoir. Preventing accumulation of bubbles improves coating concentricity and quality.

Abstract: A Charge Coupled Device (CCD) structure employing two levels of electrode metallization. The field plate electrodes are arranged in pairs with the second one of each pair partially overlapping and insulated from the first one of its pair and the first one of the next pair. The structure can be operated two-phase or four-phase with four electrodes per bit and three-phase with three electrodes per bit by providing suitable amounts of electrode overlap and suitable drive circuitry. A particularly advantageous mode of two-phase operation with four electrodes per bit is enabled by providing asymmetrical overlapping of electrodes, the second electrode of each pair overlapping the first electrode of its pair more than the first electrode of the next pair.

Abstract: Substrates for use in electrical contacts are prepared prior to plating by rapid surface melting by means of a laser beam or an electron beam. Improved microscopic surface characteristics are obtained. In a preferred embodiment, improved macroscopic surface roughness characteristics are also obtained by shorter-duration melting, typically by means of a pulsed YAG laser. Gold which has been electroplated onto copper alloys prepared by this technique has shown improved resistance to sulfur and chlorine corrosive atmospheres. This allows, for example, a thinner layer of a protective metal to be used to obtain a given degree of protection.

Abstract: A model relating obstruction fading to meteorological variables allows more precise prediction of the optimum height of microwave antenna systems. This allows the annual outage time for a circuit to be held to less than a specified maximum value, while at the same time minimizing construction costs by avoiding excessive tower heights. The predictions are especially improved over prior art engineering assumptions in coastal regions.

Abstract: It has been found that the dielectric function .epsilon.(.nu.) of materials is strongly dependent on the microstructure of the material, i.e., on the volume fractions that are crystalline, amorphous, and void, respectively. This sensitivity makes it possible to conveniently and nondestructively determine by optical methods, typically a form of spectroscopic ellipsometry, the microstructure of layers of material that are typically bounded by a free surface. The determination of actual volume fractions is made by fitting the result of a model calculation, typically in an effective medium approximation, to the measured dielectric function over an appropriate range of frequencies, e.g. frequencies corresponding to photon energies of approximately 1.5 eV-6 eV. Alternatively, the measured dielectric function, or selected features or functions thereof, can be compared to preselected standard values.

Abstract: The specification describes radiation cured coatings suitable for coating fiber lightwaveguides. The coatings are relatively low modulus materials that remain rubbery throughout normal environmental temperature ranges. An exemplary coating composition comprises an oligomeric resin, which is a condensation product of a mixture of polypropylene glycols and two units of a O-hydroxy-ethylacrylate N-C aliphatic urethane, mixed with an oligomeric liquid which is a dimethylacrylate of a polyethylene glycol of molecular weight larger than 600, a monomoneric triacrylate, such as trimethylolpropane triacrylate and a photoinitiator. The coatings are free of nomoneric ingredients.

Abstract: Conductor-clad composites are advantageously fabricated using molding compounds and associated processing techniques. The conductive cladding is applied and bonded to the composite during the molding process. The conductor-clad composite may be used as printed wiring board, and in this embodiment results in improved physical, chemical, mechanical, and electrical properties.

Abstract: A new family of rare earth-rhodium-tin intermetallic compounds, with the representative formula (RE)Rh.sub.x Sn.sub.y, has been synthesized in single crystal form. The compounds containing the heavier rare earths are superconducting and those with the lighter rare earths are generally magnetic. The compound ErRh.sub.1.1 Sn.sub.3.6 exhibits reentrant superconductivity with T.sub.c =0.97 K and T.sub.m =0.57 K as determined from ac magnetic susceptibility measurements. The synthesis and X-ray characterization of the series are described and the results of electrical resistivity, upper critical magnetic field, magnetic susceptibility, specific heat and neutron scattering measurements on the Er compound are given.

Abstract: A method and apparatus are shown for precision distance or displacement measurement using a light source and a detector. A light emitting diode or laser are typical sources, and a photodiode or phototransistor are typical detectors. Light from the source is directed towards the detector directly, or reflected onto the detector by a reflective surface. By tilting the axis of the light source and detector, high sensitivity is possible. The effect of the tilted axes may be obtained by the use of two reflective surfaces. Typical resolution is on the order of 5 microinches over a range of 50,000 microinches (i.e., one part in 10.sup.4) using simple associated electronics, with higher resolution possible.

Abstract: Method and apparatus for high-sensitivity (.alpha..ltorsim.10.sup.-6 cm.sup.-1) optoacoustic (OA) spectroscopy of substantially transparent bulk condensed matter. Part of the sample to be investigated is irradiated by pulses of radiation, typically from a pulsed dye laser. The small amount of energy absorbed by the sample causes thermal expansion of the irradiated region, resulting in cylindrical stress waves being radiated from that region. These stress waves can be observed with appropriate detection means at a location remote from the source. The method is applicable to essentially transparent liquids, and solids, and to absorptive solids suspended in liquids, and the like. Possible choices of probe radiation are not only the conventional ones of visible, near UV, and near infrared electromagnetic radiation, but also, for instance, .gamma.-rays, x-rays, vacuum UV, and far infrared.

Abstract: The specification describes a video storage system employing a unique memory tube. The tube employs a single read-write electron beam. The storage target is an insulating grid formed directly on a semiconductor substrate. Since the grid is supported, it can be made very fine and the processing advantageously uses photolithographic techniques.

Abstract: AlPO.sub.4 crystals are isomorphic with quartz and are expected therefore to have several crystal orientations in which the elastic (piezoelectric) constants are relatively insensitive to temperature. The piezoelectric coupling coefficients of AlPO.sub.4 are approximately three times those of quartz. Hydrothermal growth techniques to date have been marginal, and all have employed H.sub.3 PO.sub.4 as the hydrothermal solution. We describe using HCl as the hydrothermal solution and demonstrate the superiority of HCl from the standpoint of solubility and consequent crystal growth rate.

Abstract: The plasma growth rate of native layers, such as oxide and nitride, on silicon is enhanced by the addition of fluorine. An increase in growth rate is obtained, and the oxide growth rates on doped and undoped portions of the silicon substrate are substantially the same. The fluorine is typically added by means of a fluorinated compound, typically CF.sub.4, comprising 0.01 to 5 molecular percent of the plasma. Lower substrate temperatures, typically less than 600 degrees C., may be used, resulting in less warpage of the wafer and less diffusion of dopants.

Abstract: The lifetime of minority carriers in semiconductor materials is measured by a noncontacting steady-state method adapted for monitoring of the condition of wafers during device manufacture. The method comprises coupling the sample into an LC resonant circuit which is the frequency-determining portion of a marginal-oscillator adapted to maintain either a constant amplitude RF signal, or be driven by a constant current generator, and measuring either the current required to so maintain the signal, or the difference in RF voltage, either of which is related to the sample's conductivity. Illuminating the sample with light of appropriate frequency from an intermittent source modulates the conductivity, and the difference in the steady-state values of conductivity in the illuminated and the dark condition is proportional to the minority carrier lifetime. Exemplary apparatus has a lifetime resolution of about 0.1 .mu.sec, with a measurement time of 0.4 sec, and a sampled area of about 0.3 cm.sup.2.

Abstract: A hydrolysis method of purifying silicon tetrachloride is shown that reduces losses in optical fibers made from silica produced therefrom. Water is added to impure liquid silicon tetrachloride, which forms a gel which is then separated from the remaining SiCl.sub.4. Metal impurities, OH-containing impurities, and SiHCl.sub.3 are removed by this process. In a preferred embodiment, the water is added by bubbling a wet gas through the SiCl.sub.4. A residual amount of OH containing impurities and HCl is left after the hydrolysis, which impurities may be further removed by a refluxing technique.

Abstract: Gold plated surfaces are inspected by means of reflected light in the wavelength range of 450 to 575 nanometers to give a sensitive indication of surface conditions. This test automates the visual inspection for "brown gold" and is advantageously used in continuous strip gold plating operations. The technique may be used as a quality control check or as a process control to correct non-optimum process parameters that lead to degradation of gold surface conditions. In a preferred embodiment, the reflected light from the surface being inspected is compared with light reflected from a reference surface. Alternately, a separate wavelength band, typically 700 to 800 nanometers, is reflected from the surface being inspected and compared to the reflected light in the 450 to 575 nanometer wavelength band.

Abstract: Method and apparatus for high-sensitivity optoacoustic (OA) spectroscopy of condensed matter in thin layer form. The layer to be investigated is to be in intimate contact with a solid substrate that is essentially transparent to the probe radiation, and that is capable of transmitting ultrasonic vibrations. Intermittent probe radiation, focused to a diameter typically 10.sup.-3 -1 cm when incident on the layer, cause local heating and dimensional change in the irradiated region of the layer. The dimensional change of that region causes deformation of the adjacent substrate material, the irradiated layer region thereby becoming a source of ultrasonic waves that are spreading out in the substrate from the source region, and which can be observed with appropriate detection means at a location remote from the source.

Abstract: Multilayer printed wiring boards are conventionally laminated using epoxy adhesives. When the boards are drilled, a residual smear often remains within the drilled holes. This smear prevents proper through plating of the holes and the layers are left without some of the intended interconnections. In the past, the residual smear was removed by wet etching. A technique is described using plasma etching with the conductive surface layers of the drilled boards as the electrodes to generate the plasma. The plasma forms directly within the holes and effectively removes the smear. A dielectric material in contact or close proximity to the perimeter of each board provides uniformity of treatment over the panels.

Abstract: The construction of complex electrical circuits is simplified by performing all interconnections on one side of a component-receiving board, using slotted beam insulation-piercing connectors. Boards with or without metallization patterns are adaptable to the basic approach. Using boards with an X-Y pattern of holes arranged in columns, slotted beam connector elements are readily pressed into one side; and corresponding circuit elements such as dual-in-line packs plugged from the other side into the connector elements. The system is enhanced by a tool which feeds insulated conductor from a source and into selected slotted beams. The tool includes a retractable knife or a retractable cutter with which a given wire run may be terminated. For the manual mode, a sequence of wiring is indicated to an operator by stepping of a laser beam which illuminates successive slotted beams to be connected.