Polycrystalline silicon and method of casting the same

Abstract

Casting polycrystalline silicon includes placing a bottomless cooling crucible divided at least partially in the axis direction into a plurality of parts in the peripheral direction and having an inner surface coated with a release agent containing nitrogen, in an induction coil of a chamber charged with an inert gas; melting a raw material of polycrystalline silicon in the bottomless cooling crucible by electromagnetic induction heating using the induction coil; and pulling out the molten silicon downward while cooling and solidifying it. Pullout of the solidified molten silicon is performed through adjusting the carbon concentration of the molten silicon to 4.0×1017 atoms/cm3 or more to 6.0×1017 atoms/cm3 or less, the oxygen concentration thereof to 0.3×1017 atoms/cm3 or more to 5.0×1017 atoms/cm3 or less, and the nitrogen concentration to 8.0×1013 atoms/cm3 or more to 1.0×1018 atoms/cm3 or less.

Dependencies are inferred from the claim text.