Abstract: A head unit device for controlling motion of an object includes a chamber filled with a shear thickening fluid (STF) and a piston. The piston is housed within the chamber and exerts pressure against the STF from a force applied to the piston from the object. The STF is configured to have a decreasing viscosity in response to a first range of shear rates and an increasing viscosity in response to a second range of shear rates. The piston includes at least one piston bypass between opposite sides of the piston that controls flow of the STF between the opposite sides of the piston to selectively react with a shear threshold effect of the first range of shear rates or the second range of shear rates.

Abstract: Ion beam apparatus provides beam blanking by utilizing an aperture through which the beam passes during unblanked periods, and elements for deflecting the beam during blanking so that the beam is deflected away from the aperture. Electrodes between the aperture element and the deflecting elements generate a potential exceeding the kinetic energy of charged particles emitted from the aperture element due to ions striking the aperture element during blanking. Charged particles emitted from the aperture element are thus prevented from striking the beam deflecting elements, thereby reducing hydrocarbon cracking, insulator accumulation, and charge accumulation on the deflecting elements. Beam stability is thereby enhanced. Charged particles emitted from the aperture element are also returned to the aperture element, so that an accurate measure of ion beam current is obtained by measuring current flow to the aperture element.

Abstract: An apparatus for generating a localized, non-contact vacuum seal at a selected process region of a workpiece surface includes a vacuum body with a workpiece-facing surface having a plurality of concentric grooves and a central bore thorugh which a process energy beam can be transmitted. A method of generating a localized vacuum seal includes placing the vacuum body into selected proximity with the process region of the workpiece surface, and differentially evacuating the grooves, thereby defining differentially pumped vacuum chambers which reduce the influx of atmospheric particles to the process region. A selected control gas can be introduced into a vacuum body groove to further reduce the influx of atmospheric particles to the process region, and selected process gases can be introduced into the vacuum body to react with the process beam.

Abstract: An apparatus is described for allowing an ion beam and an electron beam to travel toward a predetermined region of a substrate surface during the sputter etching and imaging of insulating and other targets while preventing deflection of the electron beam by sources of stray electrostatic fields on the substrate surface. A metal shield is provided having a funnel-shaped portion leading to an orifice. The incident finely focused ion beam, together with the electron beam, which is used to neutralize the charge created by the incident ion beam, pass to the target through the orifice. The shield also physically supports a gas injection needle that injects a gas through the orifice toward the predetermined region.

Abstract: An ion beam treatment system for treating silicon wafers placed in the ion beam path. A rotatably mounted wafer pedestal has a plurality of wafer supporting substrates spaced about the pedestal. The substrates are constructed from an elastomer that is chosen for its ability to transfer heat generated by ion collision with the wafers away from the wafers. Each wafer substrate defines a series of elongated depressions across its surface. Certain of these depressions are connected to a pressure source at a wafer loading/unloading station to help acquire the wafers during loading and to facilitate removal of the wafers during unloading. Other depressions vent the interface between the wafers and the substrate to atmosphere to avoid undue pressure build-up on the wafers as they lift off the substrate.

Abstract: In electronic devices for measuring pressures in vacuum systems, the metal elements which undergo thermal deterioration are made readily replaceable by making them parts of a simple plug-in unit. Thus, in ionization gauges, the filament and grid or electron collector are mounted on the novel plug-in unit. In thermocouple pressure gauges, the heater and attached thermocouple are mounted on the plug-in unit. Plug-in units have been designed to function, alternatively, as ionization gauge and as thermocouple gauge, thus providing new gauges capable of measuring broader pressure ranges than is possible with either an ionization gauge or a thermocouple gauge.

Abstract: Apparatus and method for detecting leakage in a vacuum system involves a moisture trap chamber connected to the vacuum system and to a pressure gauge. Moisture in the trap chamber is captured by freezing or by a moisture adsorbent to reduce the residual water vapor pressure therein to a negligible amount. The pressure gauge is then read to determine whether the vacuum system is leaky. By directing a stream of carbon dioxide or helium at potentially leaky parts of the vacuum system, the apparatus can be used with supplemental means to locate leaks.

Abstract: An ion gauge having a reduced "x-ray limit" and means for measuring that limit. The gauge comprises an ion gauge of the Bayard-Alpert type having a short collector and having means for varying the grid-collector voltage.The "x-ray limit" (i.e. the collector current resulting from x-rays striking the collector) may then be determined by the formula: ##EQU1## where: I.sub.x ="x-ray limit",I.sub.l and I.sub.h =the collector current at the lower and higher grid voltage respectively; and,.alpha.=the ratio of the collector current due to positive ions at the higher voltage to that at the lower voltage.

Abstract: Simple apparatus for analyzing trace impurities in a gas, such as helium or hydrogen, comprises means for drawing a measured volume of the gas as sample into a heated zone. A segregable portion of the zone is then chilled to condense trace impurities in the gas in the chilled portion. The gas sample is evacuated from the heated zone including the chilled portion. Finally, the chilled portion is warmed to vaporize the condensed impurities in the order of their boiling points. As the temperature of the chilled portion rises, pressure will develop in the evacuated, heated zone by the vaporization of an impurity. The temperature at which the pressure increase occurs identifies that impurity and the pressure increase attained until the vaporization of the next impurity causes a further pressure increase is a measure of the quantity of the preceding impurity.