PROCESS FOR CONTINUOUS PRODUCTION OF POLYCRYSTALLINE HIGH-PURITY SILICON GRANULES

• Main Authors: WEIDHAUS DIETER, HAUSWIRTH RAINER, HERTLEIN HARALD
• Format: Patent
• Language: English
• Published: 13.11.2008
• Subjects: CHEMISTRY; COMPOUNDS THEREOF; INORGANIC CHEMISTRY; METALLURGY; NON-METALLIC ELEMENTS

PROBLEM TO BE SOLVED: To continuously produce polycrystalline high-purity silicon granules by depositing a reaction gas on silicon granules in a vortex motion floor reactor. SOLUTION: In a reactor provided with a reaction space composed of at least two adjoining zones, the lower zone is weakly fluidized by introducing a silicon-free gas into silicon granules through a plurality of nozzles uniformly distributed as possible, the upper zone is heated by a heating device provided at the outside of a wall, a silicon-containing reaction gas is jetted at a speed higher than that in a gas jet orientating to the vertical direction upwardly into the formed reaction zone by one or more nozzles and is surrounded by a vortex motion floor forming bubbles at the upper part of the nozzles, so as to form a local reaction gas jet, the silicon-free gas is cracked on the surfaces of the grains at the inside of the reaction gas jet, so as to cause the growth of the grains, the reaction gas is introduced till almost chemical equilibrium reaction is made still, and the silicon contained in the reaction gas is deposited on the silicon granules. COPYRIGHT: (C)2009,JPO&INPIT