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.

Systems and methods for forming an ingot from a melt are disclosed. A system includes a crucible defining a cavity for receiving the melt, and a first and second barrier to inhibit movement of the melt. A first passageway and a second passageway are arranged to allow the melt located within an outer zone to move into and through a transition zone and into an inner zone. Conditioning members are placed in at least one of the zones and arranged to contact the melt to reduce the number of micro-voids in the melt.

The invention relates to a method for producing a strand from a monotectic alloy which is made of multiple constituents and in which drops of a primary phase are distributed in a uniform manner in a crystalline matrix in the solidified state. The uniform distribution can be achieved during the production process using the following method steps: a) melting the alloy constituents which consist of at least one matrix component and components that form the primary phase and heating the constituents to a temperature at which a single homogeneous phase exists; b) transporting the melt (2) in the form of strands in a transport direction which is inclined towards the horizontal at a transport speed; c) cooling the melt (2) while transporting the strand lower face perpendicularly to the transport direction in order to form a crystallization front when transporting in a cooling zone; d) setting the cooling intensity, the inclination of the transport direction, and the transport speed such that a horizontal crystallization front is formed and the Marangoni force produced by cooling and forming the primary phase in the form of drops is oriented anti-parallel to the gravitational force such that the drops of the primary phase in the matrix component move in the direction of the gravitational force; and e) drawing the alloy which has been solidified into the strand (9) out of the cooling zone.

An improved system based on the Czochralski process for continuous growth of a single crystal ingot comprises a low aspect ratio, large diameter, and substantially flat crucible, including an optional weir surrounding the crystal. The low aspect ratio crucible substantially eliminates convection currents and reduces oxygen content in a finished single crystal silicon ingot. A separate level controlled silicon pre-melting chamber provides a continuous source of molten silicon to the growth crucible advantageously eliminating the need for vertical travel and a crucible raising system during the crystal pulling process. A plurality of heaters beneath the crucible establish corresponding thermal zones across the melt. Thermal output of the heaters is individually controlled for providing an optimal thermal distribution across the melt and at the crystal/melt interface for improved crystal growth. Multiple crystal pulling chambers are provided for continuous processing and high throughput.

Methods for producing single crystal silicon ingots by Continuous Czochralski (CCz) are disclosed. One or more plates are added to the outer melt zone of a crucible assembly such that the plates are disposed on the initial charge of solid-state silicon. The silicon is melted and the plates float on the silicon melt. When silicon is added to the outer melt zone to replenish the melt during ingot growth, the silicon contacts the plates rather than falling directly into the melt in the outer melt zone. The silicon melts and falls through openings that extend through the thickness of the plates.

Methods for forming a unitized crucible assembly for holding a melt of silicon for forming a silicon ingot are disclosed. In some embodiments, the methods involve a porous crucible mold having a channel network with a bottom channel, an outer sidewall channel that extends from the bottom channel, and a central weir channel that extends from the bottom channel. A slip slurry may be added to the channel network and the liquid carrier of the slip slurry may be drawn into the mold. The resulting green body may be sintered to form the crucible assembly.

Methods for producing single crystal ingots having doped axial resistivity regions with different resistivities and methods for producing such ingots are disclosed. In some embodiments, first and second target resistivities are determined for first and second doped axial regions. The melt is contacted with a seed crystal and pulled away from the melt to grow a single crystal ingot having the first and second doped axial regions. The addition of dopant to the melt is controlled such that the first doped axial region has the first target resistivity and the second doped axial region has the second target resistivity.

Methods for growing a reduced dislocation crystal ingot in an ingot growing system are disclosed. The system has a first crucible with a first base and a first sidewall extending upward from the first base to define an outer cavity. The method includes placing a weir in the outer cavity, placing a second crucible on the weir, placing feedstock material into the outer cavity, and melting the feedstock material to allow movement of the melt from the outer cavity inward of an intermediate cavity and into an inner cavity.

A method for recharging a crucible with polycrystalline silicon comprises adding flowable chips to a crucible used in a Czochralski-type process. Flowable chips are polycrystalline silicon particles made from polycrystalline silicon prepared by a chemical vapor deposition process, and flowable chips have a controlled particle size distribution, generally nonspherical morphology, low levels of bulk impurities, and low levels of surface impurities. Flowable chips can be added to the crucible using conventional feeder equipment, such as vibration feeder systems and canister feeder systems.

A system for growing an ingot from a melt includes an outer crucible, an inner crucible, and a weir. The outer crucible includes a first sidewall and a first base. The first sidewall and the first base define an outer cavity for containing the melt. The inner crucible is located within the outer cavity, and has a central longitudinal axis. The inner crucible includes a second sidewall and a second base having an opening therein.