Abstract: A passive containment cooling system for a nuclear reactor containment vessel. Disclosed is a cooling water distribution system for introducing cooling water by gravity uniformly over the outer surface of a steel containment vessel using a series of radial guide elements and cascading weir boxes to collect and then distribute the cooling water into a series of distribution areas through a plurality of cascading weirs. The cooling water is then uniformly distributed over the curved surface by a plurality of weir notches in the face plate of the weir box.

Abstract: A composite panel assembly for walk-in coolers and freezers and similar structures has a thickness of low strength insulation sandwiched between two facings. A reinforcing structural member is bonded to the insulation side of one of the facings and extends across at least about half of the thickness of the insulation but is spaced from the opposite facing. The reinforcing member does not provide a direct thermal path between facings; thus preventing condensation on the facing during high humidity and/or low temperature conditions.

Abstract: A porch, patio or lawn swing is safety grounded when its rider merely steps onto or off of stands on a platform extending below and forwardly of the swing seat. The platform is supported from the seat by a bracket. Preferably, the platform is pivotally supported. A spring is attached to the platform for urging the platform upwardly from the ground. When the rider is seated, the spring raises the platform from the ground and the rider may push on the platform to move the swing.

Abstract: A wafer boat transfer tool has an upper fork and a lower fork which may be differently configured for supporting wafer boats in different ways. The same tool may be used to transfer boats in one or more steps from locations where they are supported in one way to other locations where they are supported in the same or a different way. Also, the tool may be used to transfer more than one boat at a time without excessive travel in a direction parallel to the boat loader axis.A versatile wafer designed for use with two different forks of the tool may be utilized with different boat loaders and a common wafer transfer machine and in-process storage nests.

Abstract: Semiconductor wafers in plastic cassettes are loaded into (and later unloaded from) an input/output station serving a CVD furnace and thereafter the cassettes are non-manually transported by a programmable elevator to and from a flat-finder, a wafer transfer machine (where the wafers are transferred to a boat) and in-process storage. The boats are non-manually transported by a second programmable elevator to and from the wafer transfer machine, in-process boat storage and a boat loader (or process chamber directly). The cassettes can be loaded or unloaded while one or both of the elevators are operating. Up to eight human assisted steps are reduced to only two such steps.

Abstract: Empty wafer cassettes are stored on a transfer stand having one or more storage locations on a post which extends below a wafer comb while the wafers are being processed. Each storage location generally has a cross bar with spaced upward projections for receiving the leg of a cassette.

Abstract: A soft landing cantilever boat loader for loading semiconductor wafer carrying boats into a furnace process tube includes a loading station having one or more loading assemblies, an automatically controlled door associated with each loading assembly for selectively closing an end of the process tube and a microcomputer based control system for controlling and coordinating process operations. The loading assemblies are of a low profile configuration and each include a boat supporting, cantilevered paddle that is mounted by a quick release mechanism on a carriage which is driven along ways by a motor. A motor speed control circuit provides closed loop motor speed using a pulse width modulated motor drive. A door operating mechanism provides movement of the door along two transverse axes to assure tight sealing of the door against the tube.

Abstract: A flux-cored, gas shielded welding electrode is disclosed having a generally tubular sheath and a core defined within the sheath, wherein the core includes a slag forming system consisting essentially from about 3 to 12 percent titanium dioxide, less than about 2 percent calcium fluoride, and from about 0.1 to 1.0 percent sodium oxide, potassium oxide or other arc stabilizer, based on the total electrode weight. The electrode of the present invention further includes from about 0.003 to 0.08 percent boron based on the total electrode weight.

Abstract: A soft landing cantilever boat loader for loading semiconductor wafer carrying boats into a furnace process tube includes a loading station having one or more loading assemblies, an automatically controlled door associated with each loading assembly for selectively closing an end of the process tube and a microcomputer based control system for controlling and coordinating process operations. The loading assemblies are of a low profile configuration and each include a boat supporting, cantilevered paddle that is mounted by a quick release mechanism on a carriage which is driven along ways by a motor. A motor speed control circuit provides closed loop motor speed using a pulse width modulated motor drive. A door operating mechanism provides movement of the door along two transverse axes to assure tight sealing of the door against the tube.

Abstract: A soft landing cantilever boat loader for loading semiconductor wafer carrying boats into a furnace process tube includes a loading station having one or more loading assemblies, an automatically controlled door associated with each loading assembly for selectively closing an end of the process tube and a microcomputer based control system for controlling and coordinating process operations. The loading assemblies are of a low profile configuration and each include a boat supporting, cantilevered paddle that is mounted by a quick release mechanism on a carriage which is driven along ways by a motor. A motor speed control circuit provides closed loop motor speed using a pulse width modulated motor drive. A door operating mechanism provides movement of the door along two transverse axes to assure tight sealing of the door against the tube.

Abstract: A mass flow controller is disclosed herein having a bridge with a pair of arms positioned in good heat transfer relation with a gas stream, the flow rate of which is to be controlled and energized by a constant current generator wherein a resistance difference due to differential cooling by the gas stream is sensed by a bridge amplifier. A linearization network receives a signal from the bridge amplifier and applies one or more correction factors to the bridge amplifier signal to yield a linearized signal having a substantially linear relation to the rate of flow of the gas stream. A comparator receives the linearized signal and a user selectable set point signal and produces a comparator output signal which is sensed by a servoamplifier. The servoamplifier controls a valve which meters the rate of flow of the gas stream.

Abstract: A soft landing cantilever boat loader for loading semiconductor wafer carrying boats into a furnace process tube includes a loading station having one or more loading assemblies, an automatically controlled door associated with each loading assembly for selectively closing an end of the process tube and a microcomputer based control system for controlling and coordinating process operations. The loading assemblies are of a low profile configuration and each include a boat supporting, cantilevered paddle that is mounted by a quick release mechanism on a carriage which is driven along ways by a motor. A motor speed control circuit provides closed loop motor speed using a pulse width modulated motor drive. A door operating mechanism provides movement of the door along two transverse axes to assure tight sealing of the door against the tube.

Abstract: A process and apparatus for the low pressure, cold wall, chemical vapor deposition of refractory metals, such as tungsten on a silicon wafer. The silicon wafer is introduced into a loading lock wherein the pressure is reduced to subatmospheric pressure. The silicon wafer is transferred to a deposition chamber where it is heated to an elevated temperature. A refractory metal carbonyl vapor is introduced into the deposition chamber and dissociates to deposit a refractory metal on the silicon wafer. The wafer is transferred to an unloading lock where it is allowed to cool and is then removed.

Abstract: A process for chemical vapor deposition of borophosphosilicate glass on a silicon wafer at reduced pressure is disclosed herein. The process includes a step of placing a silicon wafer within a reactor tube. The reactor tube is evacuated to a pressure of less than 500 millitorr and is heated to a temperature of not less than 350.degree. C. and not greater than 500.degree. C. A mixture of silane, phosphine and boron trichloride gases is flowed into the reactor tube so that the mixture contacts the silicon wafer. At the same time, a quantity of oxygen is flowed into the reactor tube so that the oxygen also contacts the silicon wafer and intermixes and reacts with the silane, phosphine and boron trichloride gases to form layers of borophosphosilicate glass on the silicon wafer.

Abstract: A metallic ring rotating about a horizontal axis is parted by a cutting edge of a parting tool presented to the surface of the workpiece below its center of rotation. The parting tool is subjected to substantially constant high pressures which minimize chatter, vibration and shock. Vibrations generated during heavy duty operations are minimized by the additional step of supporting the toolholder with side plates.

Abstract: A rotatable or twist-on rail fastening assembly for securing a railway rail to an anchoring support therefor is comprised of a generally S-shaped torsional spring rail clip and a post-type mounting or chair adapted to cooperate therewith. The rail clip includes a central leg, a tie anchor portion and a rail bearing portion comprising a pair of loops spaced on opposite sides and extending from opposite ends thereof, each of the loops including an arcuate and a terminal leg. The chair is adapted to have the one loop of the S-shaped clip rotated around the post.

Abstract: A method for recovering superalloy scrap is disclosed. The method involves oxidizing superalloy scrap in an aqueous acidic medium. The aqueous acidic medium has an oxidation potential sufficient to oxidize nonferrous additive superalloy elements to insoluble oxides thereof and to oxidize major superalloy constituents to aqueously soluble species. The insoluble solids from the aqueous solution are separated when the aqueous solution is extracted with an aqueously substantially insoluble tertiary amine to form an organic phase and an aqueous phase. The aqueous phase contains essentially nickel and chromium values. The organic phase is sequentially extracted with aqueous solutions which selectively solubilize individual metal value species to form individual aqueous solutions having substantially single metal value species therein. The metal value species solutions are processed to obtain substantially pure metals.

Abstract: A silver-tin-copper-palladium alloy containing from 30 to 70% silver, 15 to 37% tin, at least 13% copper and from 0.05 to 0.95% palladium; and an amalgam thereof.