Abstract: The invention concerns a silicon designed in particular for making solar cells containing a total of impurities ranging between 100 and 400 ppm, a boron content ranging between 0.5 and 3 ppm, a phosphorus/boron content ratio ranging between 1 and 3, and a content of metal elements ranging between 30 and 300 ppm. The invention also concerns a method for making such a silicon from an oxygen- or chorine-refined metallurgical silicon containing at least 500 ppm of metal elements, and comprising: refusion under neutral atmosphere of the refined silicon, in an electric furnace equipped with a hot crucible; transferring the molten silicon, to provide a plasma refining, in an electric furnace equipped with a hot crucible; plasma refining with as plasma-forming gas a mixture of argon and of at least a gas belonging the group consisting of chlorine, fluorine, HCI and HF; casting under controlled atmosphere in an ingot mold wherein is produced segregated solidification.

Abstract: The present invention relates to a silicon refining installation, having a cold sectorized induction crucible, having its internal wall lined with a refractory material.

Abstract: The invention concerns a silicon designed in particular for making solar cells containing a total of impurities ranging between 100 and 400 ppm, a boron content ranging between 0.5 and 3 ppm, a phosphorus/boron content ratio ranging between 1 and 3, and a content of metal elements ranging between 30 and 300 ppm. The invention also concerns a method for making such a silicon from an oxygen- or chorine-refined metallurgical silicon containing at least 500 ppm of metal elements, and comprising: refusion under neutral atmosphere of the refined silicon, in an electric furnace equipped with a hot crucible; transferring the molten silicon, to provide a plasma refining, in an electric furnace equipped with a hot crucible; plasma refining with as plasma-forming gas a mixture of argon and of at least a gas belonging the group consisting of chlorine, fluorine, HCI and HF; casting under controlled atmosphere in an ingot mould wherein is produced segregated solidification.

Abstract: This plasma torch (10) for the excitation of a gas for the purpose of analyzing it comprises a tubular injector (12), intended to be connected to a source for supplying a gas to be analyzed, and an external cylindrical sleeve (14) coaxial with the injector (12) and defining a cylindrical annular channel (32) for supplying a plasma gas, intended to be connected to a corresponding supply source for the purpose of generating a plasma (P). The diameter of the injector (12) can vary.

Abstract: The invention concerns an inductive plasma torch comprising an external tube, an intermediate tube and a central injector (16) including at least a central tube (20, 21) injecting reagent and a peripheral sheathing tube (22). A gas similar to plasma gas is injected into the space between the central tube (20, 21) and the sheathing tube (22), in conditions suited for obtaining a laminar flow, said flow remaining laminar up to the plasma torch central zone. The sheathing tube emerges substantially at the first turn of the inductor coil.

Abstract: Apparatus for producing an aerosol jet comprising an atomizing means and a flow of carrier gas for entraining the particles formed.Downstream of the atomizing means, the conduit for carrying the aerosol constitutes the central passage (20) of a double nozzle (21) whose annular passage (22) receives another dry gaseous flow. This thus forms a central flow of aerosol, which is sheathed externally by a flow of dry gas.The invention is used for the analysis of solutions by spectroscopy.