Abstract: A method for estimating the likely waviness of a wafer after polishing based upon an accurate measurement of the waviness of the wafer in an as-cut condition, before polishing. The method measures the thickness profile of an upper and lower wafer surface to construct a median profile of the wafer in the direction of wiresaw cutting. The median surface is then passed through an appropriate Gaussian filter, such that the warp of the resulting profile estimates whether the wafer will exhibit unacceptable waviness in a post-polished stage.

Abstract: A method for estimating the likely waviness of a wafer after polishing based upon an accurate measurement of the waviness of the wafer in an as-cut condition, before polishing. The method measures the thickness profile of an upper and lower wafer surface to construct a median profile of the wafer in the direction of wiresaw cutting. The median surface is then passed through an appropriate Gaussian filter, such that the warp of the resulting profile estimates whether the wafer will exhibit unacceptable waviness in a post-polished stage.

Abstract: A method for producing a fully dense powder metal helical gear including placing powder metal in a preform die wherein it can be compacted axially by punches to create a gear preform having various gear profiles such as a helical profile, sintering the preform, and inserting the sintered preform into a hot forming die wherein it is impacted axially by punches to fully densify the gear preform. The densified gear can be inserted in a burnishing die where a more precise gear profile can be imparted resulting in more precise dimensions. Finishing treatments, such as rolling, shaving, heat treating, machining to length and inner diameter sizing can be subsequently performed.

Abstract: A method of producing a gear from a metallurgical powder includes molding at least a portion of the powder to provide a gear preform. The gear preform is sintered and hot formed, and subsequently may be carburized. The gear preform is resintered and cooled at a cooling rate suitable to provide a bainitic microstructure in at least a surface region of the preform. The gear teeth of the preform may be shaved to, for example, adjust dimensions, and enhance dimensional uniformity.

Abstract: A tube wall, division wall, or wing wall section (10) for a circulating fluidized bed boiler with improved erosion resistant characteristics has a reduced diameter tube section (40) adjacent the refractory covered by an abrasion resistant refractory tile (60). The refractory tile (60) is mounted to the reduced diameter tube section (40) with the upper edge of the refractory tile outside of or not extending beyond a solids fall line of solids in the fluidized bed to eliminate exposed discontinuities.

Abstract: A method of attaching and adjusting first and second members includes providing a first member having an outer surface and a second member. The second member is affixed to the outer surface of the first member at a desired axial position along the length of the first member and in a desired angular orientation. Subsequent to affixing the second member to the first member, the shape and/or dimensions of the second member is adjusted by increasing the density of at least a region of the second member. The densification may be accomplished by, for example, a mechanical working technique such roller burnishing, coining, sizing, shot peening, or laser impacting. In one embodiment of the invention, the method may is adapted to the production of combustion engine camshafts from separately provided camshaft tubes and cam lobes.

Abstract: A system for facilitating transfer of a semiconductor wafer into or out of a wafer carrier of a polishing or lapping machine without contacting a face of the wafer. The system includes a wafer transport suitable for placement above the carrier, the transport having at least one open cavity with a size and shape suitable for registering alignment with an opening of the carrier. The cavity and opening together form a compartment adapted to receive and hold the wafer. A liquid delivery conduit having an outlet located above an abrading member of the machine is arranged to deliver a liquid to a position generally beneath the transport. A method for transferring the wafer to or from the machine includes delivering liquid beneath the wafer. The wafer thereby moves between a first position resting on the abrading member and a second position spaced above the abrading member where a tool may engage the edge of the wafer for holding the wafer without contacting the face of the wafer.

Abstract: A method of fabricating a semiconductor wafer is disclosed. The method reduces the number of processing steps and produces a low cost semiconductor wafer having external gettering. The method includes slicing the wafer from a single silicon crystal ingot and etching the wafer to clean impurities and residue from slicing. Thereafter, the wafer is double side polished which creates damage on both the front and back surfaces. The damage on the front surface is then removed in a subsequent plasma assisted chemical etching step and touch polishing operation which significantly improves the flatness of the wafer. The damage on the back surface created by the double side polishing remains and getters defects from the front surface and bulk regions of the wafer.

Abstract: A CFB furnace or reactor unit is provided having enhanced circulation of the reagents finest particles. The improved circulation is achieved by recycling gas having entrained fine particles from a solids collection hopper connected to the solids separator back into the reactor. A system of one or more conduits connects the upper portion of the solids collection hopper with the reactor. The conduit system is equipped with means for recycling gas from the hopper to the reactor. The invention is an inexpensive system which permits recycling of the finest particles that would otherwise be carried over with the gas flow exiting the separator.

Abstract: A door (18) for sealing the opening (14) to a walk-in steam sterilizer is formed from a stainless steel plate (50), sized to cover the opening, and a load-bearing framework (52), which is formed from a material having a different coefficient of thermal expansion to that of the plate, such as carbon steel. The framework includes a set of horizontally-spaced I beams (60) which are connected together at their ends by an outer frame (64). The framework is flexibly connected to an exterior surface of the plate by a number of flexible joints (56), such as carbon steel straps. The straps are welded at either end to the plate to form loops. The I beams are supported in the loops. As the temperature inside the sterilizer changes, causing the components of the door to expand or contract, the framework and the plate are able to expand or contract at different rates without resulting in bowing or other distortion of the door. Sets of rollers (22, 24) are rotatably mounted to upper and lower ends of the outer frame.

Abstract: A system for stabilizing moisture content of soil around and beneath the foundation of a building. The system includes a source of pressurized water; one or more conduits buried in the soil around the building foundation, at least a portion of soil conduit being pervious to water, allowing water therein to enter said soil; and a remotely operated valve connecting the source of water to the conduits to permit or prevent flow of water, respectively, from the source of water to the conduits. A controller is operatively connected to the remotely operated valve for transmitting signals to the valve for opening and closing thereof in a predetermined time cycle. At least one soil moisture sensitive device is operatively connected to the controller and/or the valve for interrupting signals transmitted to the valve, to prevent opening of the valve when the moisture content of the soil exceeds a predetermined amount.

Abstract: A guidance assembly (28) guides a door (22) to a cabinet (10) while it is moved between an open position, in which access to an interior chamber is provided through an opening (16) in the cabinet, and a closed position, in which the door covers the opening. The guidance system includes four pairs of rollers (32, 34) which are mounted to upper and lower horizontal sides of the door. The rollers roll along upper and lower horizontal tracks (38, 42) which are mounted to an exterior wall (18) of the cabinet, adjacent upper and lower ends of the opening. Leading and trailing recesses (56, 62) are defined in the tracks to receive the rollers when the door is in the closed position. Leading pairs (32) of the rollers have shorter shafts (52) than corresponding trailing pairs (34) of the rollers. The trailing recesses (62) are further from the door than the leading recesses (56), leaving a narrow strip of land (64) between the trailing recesses and the door.

Abstract: A semiconductor wafer scrubbing and drying apparatus is capable processing wafers in a vertical orientation from start to finish. The apparatus moves the wafers in a generally vertical direction from an entry station of the apparatus to a dryer of the apparatus. The wafers enter the apparatus in a cassette and exit in another cassette in the same order as they were in the entry cassette to preserve individual wafer identity. The apparatus is constructed so that the compartment in which the wafers are handled is isolated and the components handling the wafers in that compartment are made of a fluorinated plastic. The actuators driving the motion of the wafer handling components are located in another compartment. A rinsing device in the wafer handling compartment is activated and deactivate for rinsing one of the wafers without the use of valves in the rinse line.

Abstract: A gas burner assembly for a poultry house heater having a head that is fabricated from a metal stamping process. The gas burner has a venturi tube which extends between a burner orifice and a burner head. The burner head is manufactured from a top plate and a bottom plate. The top and bottom plates define about forty upper half and lower half burner ports wherein the lower half ports of the bottom plate are in registry with the upper half ports in the top plate to define the ports for the gas burner. The interior of the head is shaped to form a chamber around the junction with the venturi tube having a height greater than said ports, and the interior surface of the head is smooth and free of sharp edges. The top and bottom plates are mechanically connected by a series of tabs and slots formed on the top and bottom plates.

Abstract: A box handling apparatus having particular application in the packaging of semiconductor wafers, includes a box opening assembly which can unlatch a lid from a bottom of the box and separate the lid from the bottom. Arms can grip an article, such as a wafer cassette, in the bottom of the box and lift it out. The cassette can be loaded, or wafers already in the cassette unloaded. The apparatus can replace the loaded cassette in the bottom of the box and latchingly re-engage the lid.

Abstract: A suspension apparatus is provided for hanging a space heater having a generally circular top cover for use in a livestock or poultry house. The suspension apparatus is designed to decrease the distance from a support cable end to the top of a space heater, thereby increasing the clearance between the space heater and the floor of the animal house. The suspension apparatus includes a Y-shaped member having a first arm and a second arm that are substantially equal in length. The Y-shaped member additionally includes a third arm that is shorter than the first and second arms. The first, second and third arms of the Y-shaped member are substantially in a common plane. An extension arm is provided, which is slidably mounted on and in parallel relation to the third arm of the Y-shaped member. The first and second arms of the Y-shaped member and the extension arm are engageable with apertured tabs typically provided on a top cover of a space heater. A hook element is fashioned on the extension arm.

Abstract: A novel pathovar has been isolated and purified, which pathovar most resembles Alternaria zinniae Pape, but has a host specificity for Italian thistle. By administering spores of this pathovar, called Alternaria sp., particularly shortly after emergence, Italian thistle growth is substantially inhibited.The spores of Alternaria sp. described in the subject invention have been deposited at the A.T.C.C. on Aug. 17, 1984 and given Accession No. 20723.

Abstract: A solid state klystron comprising a switching regulator, power source, tuning adapter, and solid state oscillator utilizing supply voltages identical to those of a standard tube-type klystron.