Patent ID: 8277558

Claim:
A czochralski apparatus for growing crystals, comprising: a melting pot having a heating part to dissolve raw salts at a controlled temperature; an ascending or descending device located at the center of a bottom end of the melting pot to move the melting pot upward or downward; a pulling bar located at the center of an upper end of the melting pot to take out desired pure salt crystals from molten raw salt containing impurities; a first fixation screw assembly for fixing salt crystals being in contact with the molten raw salts containing impurities; and a second fixation screw assembly for fixing salt crystals being in contact with the molten raw salts containing impurities, wherein each of the first and second fixation screw assembly includes a fixation screw for salt crystals mounted on the bottom end of the pulling bar capable of rotating, a thread portion for salt crystals formed on an outer surface of the fixation screw, and an exhaust port formed at an upper end portion of the fixation screw so as to enable the molten raw salts to be easily penetrated into the fixation screw, wherein the first and second fixation screw assemblies are apart from each other with a gap therebetween.