Abstract: A solidified mass for a high-purity multicrystal silicon material that is preferably applicable to producing crystal type silicon ingots for photo voltaics, and a process for producing the solidified mass are provided. The mass of silicon solidified from molten state is a solidified mass produced by dropping molten silicon into a receiving vessel and allowing the vessel to receive the molten silicon, said solidified mass containing bubbles and having (i) an apparent density of not less than 1.5 g/cm3 and not more than 2.2 g/cm3 and (ii) a compressive strength of not less than 5 MPa and not more than 50 MPa. The process for producing a mass of silicon solidified from molten state includes the steps of dropping molten silicon into a receiving vessel and allowing the vessel to receive the molten silicon, wherein the surface temperature of the vessel for receiving the molten silicon is not lower than 0° C. and not higher than 1000° C.

Abstract: To provide an apparatus for producing silicon capable of recovering silicon sufficiently in a recovery container even if the silicon deposited in a reaction container solidifies in the shape of an anthill. [Means for Solution] The apparatus for producing silicon has means for moving a recovery container 14 in a reaction container body 2. The moving means includes a support shaft 18 for supporting a bottom wall 14b of the recovery container 14 and a drive unit 17 for rotating the support shaft 18, which are provided for the recovery container 14. The support shaft 18 is deviated from the position of the center portion of the opening 7a on the lower end side of the reaction tube 7 so that the support shaft 18 suitably rotates at the time when the silicon is recovered in the recovery container 14 thereby varying the position on where the anthill is formed.

Abstract: It is an object of the present invention to prevent leakage of a raw material gas or molten silicon in a carbon columnar container which is constructed by connecting plural carbon cylindrical members to each other by a screw portion provided along the periphery of an end of each of the cylindrical members, by sealing a gap present at the connection portion through a high-reliability method that causes no cracking or the like.

Abstract: There is provided a reaction vessel whereby silicon produced can be smoothly recovered dropwise without excessive thermal load on constitutional parts of the reaction vessel, a silicon deposition feedstock gas can be reacted efficiently even when the reaction vessel is scaled up to industrial large-scale equipment, generation of silicon fine powder and silane oligomers can be suppressed, and industrial silicon production can be performed over extended periods. The tubular reaction vessel comprises a longitudinally-extending wall with a space thereinside, wherein a silicon deposition feedstock gas inflow opening and a deposited silicon discharge opening are provided at an upper portion and a lower end portion respectively, and a flow resistance-increasing region is created on a wall surface of the tubular reaction vessel that is contacted with a feedstock gas. The flow resistance-increasing region is at least one of protrudent, concave and sloped regions.

Abstract: It is an object to provide a silicon manufacturing apparatus that suppresses a silicon deposition to the bottom end portion of the reaction vessel and to a section other than the inside face of the reaction vessel except for the bottom end portion, thereby enabling a stable operation for a long time, for a silicon manufacturing apparatus that introduces a reaction gas to the inside wall of the heated reaction vessel to deposit silicon and that withdraws the deposited silicon from an opening at the bottom end portion of the reaction vessel. A first gas supply port 31 that is formed by a circular slit and that supplies a sealing gas and/or an etching gas to the bottom end portion is formed on the peripheral side around the bottom end portion of the reaction vessel.

Abstract: A solidified mass for a high-purity multicrystal silicon material that is preferably applicable to producing crystal type silicon ingots for photo voltaics, and a process for producing the solidified mass are provided. The mass of silicon solidified from molten state is a solidified mass produced by dropping molten silicon into a receiving vessel and allowing the vessel to receive the molten silicon, said solidified mass containing bubbles and having (i) an apparent density of not less than 1.5 g/cm3 and not more than 2.2 g/cm3 and (ii) a compressive strength of not less than 5 MPa and not more than 50 MPa. The process for producing a mass of silicon solidified from molten state includes the steps of dropping molten silicon into a receiving vessel and allowing the vessel to receive the molten silicon, wherein the surface temperature of the vessel for receiving the molten silicon is not lower than 0° C. and not higher than 1000° C.

Abstract: There is provided a reaction vessel whereby silicon produced can be smoothly recovered dropwise without excessive thermal load on constitutional parts of the reaction vessel, a silicon deposition feedstock gas can be reacted efficiently even when the reaction vessel is scaled up to industrial large-scale equipment, generation of silicon fine powder and silane oligomers can be suppressed, and industrial silicon production can be performed over extended periods. The tubular reaction vessel comprises a longitudinally-extending wall with a space thereinside, wherein a silicon deposition feedstock gas inflow opening and a deposited silicon discharge opening are provided at an upper portion and a lower end portion respectively, and a flow resistance-increasing region is created on a wall surface of the tubular reaction vessel that is contacted with a feedstock gas. The flow resistance-increasing region is at least one of protrudent, concave and sloped regions.

Abstract: There is provided a production process of silicon that can reutilize a receiving vessel without breaking of the receiving vessel and does not cause inclusion of impurities in silicon from the receiving vessel in contact with molten silicon. The production process of silicon comprises the steps of: depositing silicon in a solid state or molten state by contacting gas mixture of hydrogen and silanes to the surface having the temperature range of 600 to 1700° C.; melting a part or the whole of the deposited silicon, dropping the melt from a deposition surface, and receiving the dropped molten silicon in a receiving vessel, wherein said receiving vessel comprises a silicon bottom plate member(s) and a plurality of silicon side plate members that are installed upright direction from the peripheral part of the bottom plate member.