METHOD FOR PRODUCING POLYCRYSTALLINE SILICON AND POLYCRYSTALLINE SILICON FOR SOLAR CELL PRODUCED BY

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A method for producing a polycrystalline silicon wherein a silane gas as a raw material is supplied onto a red-hot seed rod in a sealed reaction furnace, to thereby subject the silane gas to pyrolysis or the reduction by hydrogen and precipitate a high purity polycrystalline silicon, characterized in that a member made of an alloy having a re-crystallization temperature of 1200˚C or higher is used as the seed rod. Preferably, the member made of an alloy having a re-crystallization temperature of 1200˚C or higher is made of Re-W, W-Ta, Zr-Nb or a titanium-zirconium-carbon added molybdenum (TZM) alloy and has a shape of a wire having a diameter of 0.5 mm or more, a sheet or a square bar having a thickness of 1 mm or more or a tube having a diameter of 1 mm or more, a thickness of 0.2 mm or more and an inner diameter of 5 mm or less. The above method needs no external heating means for heating a core material for the precipitation and adhesion of a polycrystalline silicon even in the period of an initial heating, and allows the enhanced speed of precipitation and adhesion from an initial stage of the reaction, and further allows the repeated use of the core material.