Abstract: Scrap silicon from which a profit can be obtained taking into consideration the purchase price and refining cost of scrap silicon and the expected sale price of silicon products is selectively recovered, the recovered scrap silicon is refined, and silicon which can be sold as a silicon product is manufactured.

Abstract: In a refining method for boron-containing silicon, boron-containing silicon is irradiated with an electron beam in a vacuum vessel to melt the boron-containing silicon. A boron compound-forming substance is introduced into the vacuum vessel, and boron contained in the molten silicon is formed into a boron compound. After at least a portion of the boron compound has vaporized, irradiation with the electron beam is stopped. The high-purity molten silicon can then be solidified.

Abstract: A crucible apparatus includes a hollow crucible body which is open at its upper and lower ends and a bottom plate which is formed separately from the crucible body and can close off the lower end of the crucible body. A space for receiving a molten material is formed by placing the crucible body atop the bottom plate. When molten material received in the space has solidified, the crucible body is raised off the bottom plate, and solidified material is pushed out of one end of the crucible body and removed from the crucible body.

Abstract: A method and apparatus for refining silicon which can remove impurity elements such as phosphorus and antimony as well as impurity elements such as boron and carbon using an electron beam in the same vacuum chamber are provided. Silicon is irradiated and melted with an electron beam in a low vacuum inside a vacuum vessel, a compound-forming substance such as H2O which reacts with boron or the like in the molten silicon and forms a vaporizable oxide is introduced into the vacuum chamber, and impurity elements such as boron having a low vapor pressure in a vacuum are evaporated from the molten silicon as part of the vaporizable compound. Silicon in the vacuum vessel is then irradiated with an electron beam in a high vacuum in the vacuum vessel, and impurity elements contained in the silicon having a high vapor pressure in a vacuum such as phosphorus are removed.

Abstract: A refining apparatus for scrap silicon using an electron beam which is suitable for recycling of scrap silicon which is formed during the manufacture of silicon products such as silicon wafers includes a vacuum chamber, a crucible installed within the vacuum chamber, a hearth which is installed next to the crucible within the vacuum chamber and which receives granular scrap silicon and which melts granular silicon by irradiation with an electron beam and which supplies molten silicon to the crucible, and a raw material supply apparatus which is installed within the vacuum chamber and which stores a prescribed amount of granular scrap silicon and supplies the stored granular scrap silicon via a chute.

Abstract: A method of refining scrap silicon using an electron beam includes a step of selectively preparing lumps of n-type scrap silicon containing a specific impurity element as a dopant, a step of crushing the prepared lumps of scrap silicon, a step of placing the crushed silicon into a vacuum vessel, a step of irradiating the crushed silicon which was placed into the vacuum vessel with an electron beam to melt it and vaporize at least a portion of the impurity element, and a step of solidifying the resulting silicon.

Abstract: Non-destructive testing is performed on individual pieces of scrap silicon using an energy dispersive x-ray fluorescent analyzer to determine from the obtained spectral data whether a prescribed impurity element is contained therein. The electrical resistivity of each piece of scrap silicon can be measured, and the concentration of the impurity element contained in the scrap on can be calculated from the resistivity.

Abstract: A method and apparatus for refining silicon which can remove impurity elements such as phosphorus and antimony as well as impurity elements such as boron and carbon using an electron beam in the same vacuum chamber are provided. Silicon is irradiated and melted with an electron beam in a low vacuum inside a vacuum vessel, a compound-forming substance such as H2O which reacts with boron or the like in the molten silicon and forms a vaporizable oxide is introduced into the vacuum chamber, and impurity elements such as boron having a low vapor pressure in a vacuum are evaporated from the molten silicon as part of the vaporizable compound. Silicon in the vacuum vessel is then irradiated with an electron beam in a high vacuum in the vacuum vessel, and impurity elements contained in the silicon having a high vapor pressure in a vacuum such as phosphorus are removed.

Abstract: In a method of crushing silicon blocks, a silicon block to be crushed is heated and is then forcedly cooled. Subsequently, a crushing member which contains no metal component at least on a surface thereof is made to strike the cooled silicon block to thereby crush the silicon block. Alternatively, two silicon blocks to be crushed are heated and are then forcedly cooled. Subsequently, the cooled silicon blocks are made to strike against each other, whereby the silicon blocks are crushed.

Abstract: A crucible apparatus includes a hollow crucible body which is open at its upper and lower ends and a bottom plate which is formed separately from the crucible body and can close off the lower end of the crucible body. A space for receiving a molten material is formed by placing the crucible body atop the bottom plate. When molten material received in the space has solidified, the crucible body is raised off the bottom plate, and solidified material is pushed out of one end of the crucible body and removed from the crucible body.

Abstract: Non-destructive testing is performed on individual pieces of silicon using an energy dispersive x-ray fluorescent analyzer to determine from the obtained spectral data whether a prescribed impurity element is contained therein. The electrical resistivity of each piece of scrap silicon can be measured, and the concentration of the impurity element contained in the scrap on can be calculated from the resistivity.

Abstract: In a refining method for boron-containing silicon, boron-containing silicon is irradiated with an electron beam in a vacuum vessel to melt the boron-containing silicon. A boron compound-forming substance is introduced into the vacuum vessel, and boron contained in the molten silicon is formed into a boron compound. After at least a portion of the boron compound has vaporized, irradiation with the electron beam is stopped. The high-purity molten silicon can then be solidified.

Abstract: Scrap silicon from which a profit can be obtained taking into consideration the purchase price and refining cost of scrap silicon and the expected sale price of silicon products is selectively recovered, the recovered scrap silicon is refined, and silicon which can be sold as a silicon product is manufactured.

Abstract: A refining apparatus for scrap silicon using an electron beam which is suitable for recycling of scrap silicon which is formed during the manufacture of silicon products such as silicon wafers includes a vacuum chamber, a crucible installed within the vacuum chamber, a hearth which is installed next to the crucible within the vacuum chamber and which receives granular scrap silicon and which melts granular silicon by irradiation with an electron beam and which supplies molten silicon to the crucible, and a raw material supply apparatus which is installed within the vacuum chamber and which stores a prescribed amount of granular scrap silicon and supplies the stored granular scrap silicon via a chute.

Abstract: A method of refining scrap silicon using an electron beam includes a step of selectively preparing lumps of n-type scrap silicon containing a specific impurity element as a dopant, a step of crushing the prepared lumps of scrap silicon, a step of placing the crushed silicon into a vacuum vessel, a step of irradiating the crushed silicon which was placed into the vacuum vessel with an electron beam to melt it and vaporize at least a portion of the impurity element, and a step of solidifying the resulting silicon.

Abstract: In a method of crushing silicon blocks, a silicon block to be crushed is heated and is then forcedly cooled. Subsequently, a crushing member which contains no metal component at least on a surface thereof is made to strike the cooled silicon block to thereby crush the silicon block. Alternatively, two silicon blocks to be crushed are heated and are then forcedly cooled. Subsequently, the cooled silicon blocks are made to strike against each other, whereby the silicon blocks are crushed.