| 摘要 |
PURPOSE:To obtain a polycrystalline silicon of large crystalline particle size and of less defects by forming a power layer composed of materials with high fusing point between a multilayer silicon lump and a casting mold possessing the lump, solving a problem of stress and using the casting mold several times continuously. CONSTITUTION:A quartz crucible 1 with a prescribed diameter of which inner wall is coated with nitriding silicon powder 2 of a prescribed particle size to a prescribed thickness or more is prepared, and raw materials in high purity are put in the crucible 1 and heated at a prescribed temperature to be fused. The silicon completely made a fused liquid in the crucible 1 is slowly solididies all after a prescribed period of time to be a polycrystalline silicon 3. Forming the nitriding silicon powder on the inner wall of the crucible 1 prevents a reaction of the quartz and the silicon, preventing the crucible 1 from being broken by one time use and enabling the same to be used continuously several times. |
