Abstract: A pendulum gate valve including an expandable gate which pivots when unexpanded to selectively block a vacuum or other pressure-differential passage. The valve includes a valve plate sealing one side of the passage and a ring or barrier plate abutting an opposed side of the passage when the gate member is expanded. A compression spring biases apart the valve plate and ring to close the valve by means of respective two-stage hangers attached thereto, extending along the spring, and having distal ends capturing the spring. Pneumatic pressure applied to a pneumatic cavity formed between the middles of the two-stage hangers and accommodating the spring forces apart the valve plate and ring to open the valve in the blocking position. Thereby if pressure fails, the valve fails to a sealed state. The axially movable valve or barrier plate is advantageously water cooled to allow use with a heated processing chamber.

Abstract: A Czochralski growth system is described comprising a growth chamber, a feed port, and a feed chamber comprising a container for feedstock and a feeder. The feed port is disposed in at least one side wall of the growth chamber, and the feed chamber is attached to the growth chamber at the feed port. The feeder is insertable into the growth chamber through the feed port and supplies the feedstock into the growth chamber. Preferably this system can be used for producing silicon ingots using a continuous Czochralski method.

Abstract: A Czochralski growth system is disclosed comprising a crucible, a silicon delivery system comprising a feeder having a delivery point overhanging the crucible and delivering a controllable amount of silicon into the crucible, and at least one doping mechanism controllably delivering at least one dopant material to the feeder. The system can comprise two or more doping mechanisms each loaded with a different dopant material and can therefore be used to prepare silicon ingots having multiple dopants. The resulting ingots have substantially constant dopant concentrations along their axes. Also disclosed is a method of Czochralski growth of at least one silicon ingot comprising at least one dopant material, which is preferably a continuous Czochralski method.

Abstract: The present invention relates to a method of growing a silicon ingot comprising a dopant material having a segregation coefficient of k, wherein the concentration of the dopant is axially substantially uniform throughout the ingot. The method comprises the steps of providing a crucible having an inner growth zone in fluid communication with an outer feed zone, and the inner growth zone and the outer feed zone have cross-sectional areas that are can be used to determine conditions for maintaining dopant uniformity for the specific dopant material used. A crystalline growth system for growing at least one uniformly doped silicon ingot is also disclosed.

Abstract: A Czochralski growth system comprising a growth chamber, an isolation valve, a feed chamber containing feedstock, and a feeder is described. The isolation valve is disposed in at least one side wall of the growth chamber, and the feed chamber is vacuum sealed to the growth chamber through the isolation valve. The feeder is insertable into the growth chamber through the isolation valve and supplies the feedstock into the growth chamber. Preferably this system can be used for producing silicon ingots using a continuous Czochralski method.

Abstract: Efficiency of silicon photovoltaic solar cells is increased by an annealing process for immobilizing oxygen formed in Czochralski-grown silicon. The annealing process includes a short anneal in a rapid thermal annealing chamber at a high temperature, for example, greater than 1150° C. in an oxygen-containing ambient, More preferably, the wafer is rapidly cooled to less than 950° C. without an intermediate temperature hold, at which temperature oxygen does not nucleate and/or precipitate, Subsequent processing to form a photovoltaic structure is typically performed at relatively low temperatures of less than 1000° C. or even 875° C.

Abstract: An evaporative cooling unit has an internal conduit structure with an inlet and outlet, an air blower for establishing a forced air flow through the conduit, and a plurality of nozzles that emit atomized water into the air flow. The nozzles connect to a source of water such as a pump coupled to a tap water supply. Sprayed water mixes with the forced air flow and is emitted as a mist or fog, the temperature of the air and water being reduced via evaporative cooling. The unit can form an inverted L-shape, a column or a framework, e.g., forming a pavilion. The unit can be inflatable or can be formed by rigid hollow columns and/or horizontal beams that form the air conduits and contain one or more blowers as well as piping for carrying water to the nozzles. A ball joint discharge fixture having air exhaust holes surrounding a spray nozzle allows the mixed air/water output to be directed where needed to form a refreshing cooled area, especially in the open.