Cover flux devices and methods are shown. Methods and devices are shown such that, as a solidification front moves from a cooling surface of a mold towards a surface of molten silicon substantially opposite the cooling surface, impurities are driven out of the solid silicon and into the liquid to react with a flux layer on the silicon.
A method comprises forming molten silicon (206) in a crucible (202), forming a solidified silicon (208) at a top portion of the molten silicon (206), contacting the solidified silicon (208) with glass (210), heating the solidified silicon (208) and the glass (210), sufficient to melt the solidified silicon and the glass, to provide a molten glass (212) on the molten silicon (206), and allowing the molten liquid to directionally solidify, from the bottom portion of the molten liquid toward the top portion of the molten liquid, to provide solid silicon (214) with a higher purity.
A crucible for containing molten silicon comprises at least one refractory material having at least one inner surface defining an interior for receiving a molten silicon mixture, and a lining deposited onto the inner surface, the lining comprising colloidal alumina. A method for silicon purification comprises contacting a first silicon with a solvent metal comprising aluminum, sufficient to provide a first mixture, melting the first mixture in an interior of a melting crucible to provide a molten silicon mixture, the melting crucible comprising at least one refractory material having an inner surface defining the interior of the melting crucible, coating at least a portion of the inner surface of the melting crucible with a lining comprising colloidal alumina prior to melting first mixture, cooling the molten silicon mixture, sufficient to form recrystallized silicon crystals and a mother liquor, and separating the final recrystalized silicon crystals and the mother liquor.
C30B 11/00 - Single-crystal-growth by normal freezing or freezing under temperature gradient, e.g. Bridgman- Stockbarger method
C30B 9/06 - Single-crystal growth from melt solutions using molten solvents by cooling of the solution using as solvent a component of the crystal composition
C30B 35/00 - Apparatus not otherwise provided for, specially adapted for the growth, production or after-treatment of single crystals or of a homogeneous polycrystalline material with defined structure
The present invention provides a method for purifying an inorganic compound, in particular calcium fluoride. The method includes contacting (e.g., washing) the inorganic compound with an aqueous solution, in particular hydrochloric acid.
The present invention relates to an apparatus and method for directional solidification of silicon. The apparatus can use a cooling platform to cool a portion of a bottom of a directional solidification crucible. The apparatus and method of the present invention can be used to make silicon crystals for use in solar cells.
C30B 11/00 - Single-crystal-growth by normal freezing or freezing under temperature gradient, e.g. Bridgman- Stockbarger method
C30B 28/06 - Production of homogeneous polycrystalline material with defined structure from liquids by normal freezing or freezing under temperature gradient
C30B 35/00 - Apparatus not otherwise provided for, specially adapted for the growth, production or after-treatment of single crystals or of a homogeneous polycrystalline material with defined structure
B22D 27/04 - Influencing the temperature of the metal, e.g. by heating or cooling the mould
7.
METHOD TO PURIFY ALUMINUM AND USE OF PURIFIED ALUMINUM TO PURIFY SILICON
A method comprises forming a first molten liquid from a solvent metal and sodium carbonate, contacting the first molten liquid with silicon to form a second molten liquid, cooling the second molten liquid to provide silicon crystals and a mother liquor, and separating the silicon crystals from the mother liquor.
A method that includes: (a) forming a molten liquid from a solvent metal, silicon, and an alkali magnesium halide; (b) cooling the molten liquid to provide silicon crystals and a mother liquor; and (c) separating the silicon crystals from the mother liquor.
LINING FOR SURFACES OF A REFRACTORY CRUCIBLE FOR PURIFICATION OF SILICON MELT AND METHOD OF PURIFICATION OF THE SILICON MELT USING THAT CRUCIBLE (S) FOR MELTING AND FURTHER DIRECTIONAL SOLIDIFICATION
A crucible for molten silicon comprises at least one refractory material having an inner surface and a lining deposited onto the inner surface, the lining comprising colloidal silica. A method for silicon purification comprises melting a first silicon in an interior of a melting crucible to provide a first molten silicon, the melting crucible comprising a first refractory material having at least one first inner surface defining the melting crucible interior, directionally solidifying the first molten silicon in a directional solidification mold to provide a second silicon, the directional solidification mold comprising a second refractory material having at least one second inner surface defining a mold interior, and coating at least a portion of at least one of the first inner surface and the second inner surface with a lining comprising colloidal silica.
C30B 35/00 - Apparatus not otherwise provided for, specially adapted for the growth, production or after-treatment of single crystals or of a homogeneous polycrystalline material with defined structure
The present invention relates to an apparatus and method for purifying materials using a fractional solidification. Devices and methods shown provide control over a temperature gradient and cooling rate during fractional solidification, which results in a material of higher purity. The apparatus and methods of the present invention can be used to make silicon material for use in solar applications such as solar cells.
The present invention relates to the purification of silicon. The present invention provides a method for purification of silicon. The method includes recrystallizing starting material-silicon from a molten solvent comprising aluminum to provide final recrystallized-silicon crystals. The method also includes washing the final recrystallized-silicon crystals with an aqueous acid solution to provide a final acid-washed-silicon. The method also includes directionally solidifying the final acid-washed-silicon to provide final directionally solidified-silicon crystals.
B24C 1/00 - Methods for use of abrasive blasting for producing particular effectsUse of auxiliary equipment in connection with such methods
B24C 1/08 - Methods for use of abrasive blasting for producing particular effectsUse of auxiliary equipment in connection with such methods for polishing surfaces, e.g. by making use of liquid-borne abrasives
C30B 33/00 - After-treatment of single crystals or homogeneous polycrystalline material with defined structure
The present invention relates to devices and method for textured semiconductor materials. Devices and methods shown provide a textured surface with properties that provide a high breakdown voltage. The devices and methods of the present invention can be used to make semiconductor substrates for use in photovoltaic applications such as solar cells.
H01L 31/068 - SEMICONDUCTOR DEVICES NOT COVERED BY CLASS - Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier the potential barriers being only of the PN homojunction type, e.g. bulk silicon PN homojunction solar cells or thin film polycrystalline silicon PN homojunction solar cells
The present invention relates to an apparatus and method for purifying materials using a rapid directional solidification. Devices and methods shown provide control over a temperature gradient and cooling rate during directional solidification, which results in a material of higher purity. The apparatus and methods of the present invention can be used to make silicon material for use in solar applications such as solar cells. A mold (801) is defined by a wall structure (802) and a base (804). The system (800) also includes a top heater (820) to control the thermal gradient and the cooling rate of the molten silicon (801). The wall structure (801) includes a taper in thickness from a rim of the mold (801) to an interface with the bottom (804).
C30B 28/06 - Production of homogeneous polycrystalline material with defined structure from liquids by normal freezing or freezing under temperature gradient
B22D 27/04 - Influencing the temperature of the metal, e.g. by heating or cooling the mould
Techniques for the formation of silicon ingots and crystals using silicon feedstock of various grades are described. A common feature is adding a predetermined amount of germanium to the melt and performing a crystallization to incorporate germanium into the silicon lattice of respective crystalline silicon materials. Such incorporated germanium results in improvements of respective silicon material characteristics, including increased material strength and improved electrical properties. This leads to positive effects at applying such materials in solar cell manufacturing and at making modules from those solar cells.
C30B 11/00 - Single-crystal-growth by normal freezing or freezing under temperature gradient, e.g. Bridgman- Stockbarger method
C30B 11/04 - Single-crystal-growth by normal freezing or freezing under temperature gradient, e.g. Bridgman- Stockbarger method adding crystallising materials or reactants forming it in situ to the melt
C30B 11/08 - Single-crystal-growth by normal freezing or freezing under temperature gradient, e.g. Bridgman- Stockbarger method adding crystallising materials or reactants forming it in situ to the melt every component of the crystal composition being added during the crystallisation
C30B 13/00 - Single-crystal growth by zone-meltingRefining by zone-melting
C30B 13/08 - Single-crystal growth by zone-meltingRefining by zone-melting adding crystallising materials or reactants forming it in situ to the molten zone
C30B 13/10 - Single-crystal growth by zone-meltingRefining by zone-melting adding crystallising materials or reactants forming it in situ to the molten zone with addition of doping materials
C30B 15/00 - Single-crystal growth by pulling from a melt, e.g. Czochralski method
C30B 15/02 - Single-crystal growth by pulling from a melt, e.g. Czochralski method adding crystallising materials or reactants forming it in situ to the melt
C30B 15/04 - Single-crystal growth by pulling from a melt, e.g. Czochralski method adding crystallising materials or reactants forming it in situ to the melt adding doping materials, e.g. for n–p-junction
The present invention relates to an apparatus and method for purifying silicon using directional solidification. The apparatus can be used more than once for the directional solidification of silicon without failure. The apparatus and method of the present invention can be used to make silicon crystals for use in solar cells.
C30B 28/06 - Production of homogeneous polycrystalline material with defined structure from liquids by normal freezing or freezing under temperature gradient
The present invention relates to a method of purifying silicon using a cascading dissolution and washing process. The dissolution and washing processes can contain single or multiple stages. Water and dissolving chemicals are recycled through the process towards the beginning of the process.
The present invention relates to efficient furnace capacity utilization in the production of ingots. The present invention includes a crucible and use of the same. The crucible approximately matches the interior shape of the furnace in which the ingots are produced.
Embodiments of the present invention relate to a process for obtaining silicon crystals from silicon. The method includes contacting silicon powder with a solvent metal to provide a mixture containing silicon, melting the silicon under submersion to provide a first molten liquid, contacting the first molten liquid with a first gas to provide dross and a second molten liquid, separating the dross and the second molten liquid, cooling the second molten liquid to form first silicon crystals and a first mother liquid and separating the first silicon crystals and the first mother liquid.
C30B 9/06 - Single-crystal growth from melt solutions using molten solvents by cooling of the solution using as solvent a component of the crystal composition
23.
USE OF ACID WASHING TO PROVIDE PURIFIED SILICON CRYSTALS
A method for purifying silicon wherein silicon is crystallized from a solvent metal. The method comprises the steps of providing a molten liquid containing silicon, a solvent metal and impurities, cooling the molten liquid to form first silicon crystals and a first mother liquor, separating the first silicon crystals from the first mother liquor, contacting the first silicon crystals with compound which will dissolve the first mother liquor and separating the washed crystals from the wash solution.
C22C 21/02 - Alloys based on aluminium with silicon as the next major constituent
C22C 29/18 - Alloys based on carbides, oxides, borides, nitrides or silicides, e.g. cermets, or other metal compounds, e. g. oxynitrides, sulfides based on silicides
C22C 3/00 - Removing material from non-ferrous alloys to produce alloys of different constitution
The present invention provides for methods of purifying silicon, methods for obtaining purified silicon, as well as methods for obtaining purified silicon crystals, purified granulized silicon and/or purified silicon ingots.