METHOD FOR PRODUCING POLYCRYSTALLINE SILICON, APPARATUS FOR PRODUCING POLYCRYSTALLINE SILICON, AND POLYCRYSTALLINE SILICON

摘要

PPROBLEM TO BE SOLVED: To make a silicon rod grow to thereby have a large diameter with a high growth rate and a high yield under the condition where a large amount of raw material is supplied at a high pressure while preventing the blowout of the rod. PSOLUTION: A method for producing polycrystalline silicon comprises supplying electric current to a silicon core rod in a reactor to make the silicon core rod to generate heat, supplying raw material gas including chlorosilanes to the silicon core rod, and depositing polycrystalline silicon on a surface of the silicon core rod to be grown as a rod, wherein the method comprises a first process and a second process, in the first process, a surface temperature is maintained at a predetermined range by adjusting the current value to the silicon core rod, and the raw material gas is supplied while maintaining a supply amount of chlorosilanes per square millimeter of the surface of the rod in a predetermined range until a temperature of the center portion of the rod reaches a predetermined temperature lower than the melting point of the silicon, and in the second process, a previously determined current value is set corresponding to a rod diameter and the supply amount of the raw material gas per square millimeter of the surface of the rod is decreased to maintain the surface temperature and the temperature of the center portion of the rod at predetermined ranges, under the condition where a large amount of raw material gas is supplied at a high pressure. PCOPYRIGHT: (C)2011,JPO&INPIT