Abstract: 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.

Abstract: The present invention provides for a flux composition, and the use thereof in a directional solidification for the purification of silicon.

Abstract: The present invention provides for a flux composition, and the use thereof in a directional solidification for the purification of silicon.

Abstract: The present invention provides for a flux composition, and the use thereof in a directional solidification for the purification of silicon.

Abstract: 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.

Abstract: 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 recrystallized silicon crystals and the mother liquor.