Abstract: A dopant feeding device for releasing dopant into a feeder system during doping of a crystal growing system includes a dopant container for holding the dopant, a lower valve, and an upper valve. The dopant container includes a wall defining a lower opening for releasing the dopant therethrough. The lower valve is positioned adjacent to the lower opening and is movable between a closed position that is in contact with the wall to prevent passage of dopant through the lower opening and an open position that is spaced from the lower opening to allow passage of dopant therethrough. The upper valve is positioned above and connected to the lower valve. The upper valve is disposed within the dopant container and is movable between a first position that is spaced from the dopant container and a second position that is in contact with the dopant container.

Abstract: Shell and tube heat exchangers that include a baffle arrangement that improves the temperature profile and flow pattern throughout the exchanger and/or that are integral with a reaction vessel are disclosed. Methods for using the exchangers including methods that involve use of the exchanger and a reaction vessel to produce a reaction product gas containing trichlorosilane are also disclosed.

Abstract: Methods are disclosed for inhibiting heat transfer through lateral sidewalls of a support member positioned beneath a crucible in a directional solidification furnace. The methods include the use of insulation positioned adjacent the lateral sidewalls of the support member. The insulation inhibits heat transfer through the lateral sidewalls of the support member to ensure the one-dimensional transfer of heat from the melt through the support member.

Abstract: A directional solidification furnace includes one or more movable cooling plates disposed beneath a crucible. In a first position, the cooling plates are free from contact with a crucible support positioned adjacent the crucible. In a second position, the cooling plates are in contact with the crucible support. A control system is used to control the amount of force exerted by the cooling plates against the crucible.

Abstract: A method of producing rectangular seeds for use in semiconductor or solar material manufacturing includes connecting an adhesive layer to a top surface of a template, the template including a plurality of parallel slots, and drawing alignment lines on the adhesive layer, the alignment lines aligned with at least some of the parallel slots. The method also includes connecting quarter sections to the adhesive layer such that an interface between a rectangular seed portion and a curved wing portion of each quarter section is aligned with at least one of the alignment lines drawn on the adhesive layer, and slicing each of the quarter sections to separate the rectangular seed portions from the curved wing portions.

Abstract: Silicon nitride coated crucibles for holding melted semiconductor material and for use in preparing multicrystalline silicon ingots by a directional solidification process; methods for coating crucibles; methods for preparing silicon ingots and wafers; compositions for coating crucibles and silicon ingots and wafers with a low oxygen content.

Abstract: A method of loading a crucible includes loading a first layer of polysilicon chunks into the crucible and loading a second layer of granular polysilicon into the crucible to form a polysilicon charge such that the packing density of the polysilicon charge within the crucible is greater than 0.70.

Abstract: A method of grinding an ingot for use in manufacturing a semiconductor or solar wafer is disclosed. The method includes providing an ingot including four flat sides and four rounded corner portions, each corner portion extending between an adjacent pair of the flat sides, and grinding a plurality of planar facets on each corner portion, each planar facet of the corner portion joined to an adjacent facet at a juncture and oriented such that each corner portion has a substantially arcuate shape. A wafer and ingot are also disclosed.

Abstract: A crystal pulling apparatus for producing an ingot is provided. The apparatus includes a furnace and a gas doping system. The furnace includes a crucible for holding a melt. The gas doping system includes a feeding tube, an evaporation receptacle, and a fluid flow restrictor. The feeding tube is positioned within the furnace, and includes at least one feeding tube sidewall, a first end through which a solid dopant is introduced into the feeding tube, and an opening opposite the first end through which a gaseous dopant is introduced into the furnace. The evaporation receptacle is configured to vaporize the dopant therein, and is disposed near the opening of the feeding tube. The fluid flow restrictor is configured to permit the passage of solid dopant therethrough and restrict the flow of gaseous dopant therethrough, and is disposed within the feeding tube between the first end and the evaporation receptacle.

Abstract: A directional solidification furnace includes a crucible for holding molten silicon and a lid covering the crucible and forming an enclosure over the molten silicon. The crucible also includes an inlet in the lid for introducing inert gas above the molten silicon to inhibit contamination of the molten silicon.

Abstract: Shell and tube heat exchangers that include a baffle arrangement that improves the temperature profile and flow pattern throughout the exchanger and/or that are integral with a reaction vessel are disclosed. Methods for using the exchangers including methods that involve use of the exchanger and a reaction vessel to produce a reaction product gas containing trichlorosilane are also disclosed.

Abstract: A heat exchanger system for use in a directional solidification furnace is disclosed. The heat exchanger includes a plate having a flow path formed in the plate for directing a flow of coolant. The flow path has an inlet positioned adjacent an outlet. A wall separates the inlet and the outlet of the flow path. The heat exchanger includes a cover having an opening in fluid communication with the inlet and the outlet of the flow path. An inner conduit is connected to the inlet of the flow path and an outer conduit is connected to the outlet of the flow path.

Abstract: Methods and systems for evaluation of wafers are disclosed. One example method includes illuminating a multi-crystalline wafer according to a plurality of lighting parameters, capturing a plurality of images of the multi-crystalline wafer, stacking and projecting the plurality of images to generate a composite image, analyzing the composite image to identify one or more grains of the multi-crystalline wafer, and generating a report based on the analysis of the composite image. The multi-crystalline wafer is illuminated according to a different one of the plurality of lighting parameters in at least two of the plurality of images.

Abstract: Systems and methods are disclosed for monitoring and controlling silicon rod temperature. One example is a method of monitoring a surface temperature of at least one silicon rod in a chemical vapor deposition (CVD) reactor during a CVD process. The method includes capturing an image of an interior of the CVD reactor. The image includes a silicon rod. The image is scanned to identify a left edge of the silicon rod and a right edge of the silicon rod. A target area is identified midway between the left edge and the right edge. A temperature of the silicon rod in the target area is determined.

Abstract: A method of producing rectangular seeds for use in semiconductor or solar material manufacturing includes connecting an adhesive layer to a top surface of a template, the template including a plurality of parallel slots, and drawing alignment lines on the adhesive layer, the alignment lines aligned with at least some of the parallel slots. The method also includes connecting quarter sections to the alignment layer such that an interface between a rectangular seed portion and a curved wing portion of each quarter section is aligned with at least one of the alignment lines drawn on the adhesive layer, and slicing each of the quarter sections to separate the rectangular seed portions from the curved wing portions.

Abstract: A method for machining a profile into a silicon seed rod using a machine. The silicon seed rod is capable of being used in a chemical vapor deposition polysilicon reactor. The machine includes a plurality of grinding wheels. The method includes grinding a v-shaped profile into a first end of the silicon seed rod with one of the plurality of grinding wheels and grinding a conical profile in a second end of the silicon seed rod with another of the plurality of grinding wheels.

Abstract: Processes for suppressing minority carrier lifetime degradation in silicon wafers are disclosed. The processes involve quench cooling the wafers to increase the density of nano-precipitates in the silicon wafers and the rate at which interstitial atoms are consumed by the nano-precipitates.

Abstract: Methods for producing muticrystalline silicon ingots by use of a Czochralski-type crystal puller and pulling assemblies that include a plurality of seed crystals for pulling multicrystalline silicon ingots.

Abstract: A tool for harvesting polycrystalline silicon-coated rods from a chemical vapor deposition reactor includes a body including outer walls sized for enclosing the rods within the outer walls. Each outer wall includes a door for allowing access to at least one of the rods.

Abstract: A method of producing rectangular seed bricks for use in semiconductor or solar manufacturing is disclosed. The method includes connecting an alignment layer to a top surface of a template, drawing alignment lines on the alignment layer to demarcate a plurality of nodes, connecting cylindrical rods to the alignment layer such that a center of each rod is aligned with a corresponding node, and slicing through the rods and the alignment layer with a wire web to produce rectangular seed bricks.