| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a large-size polycrystalline silicon ingot capable of reducing a crystal defect density or preventing a crack easily and inexpensively, and to provide a polycrystalline silicon ingot obtained thereby, and application thereof.SOLUTION: In this method for producing a polycrystalline silicon ingot by unidirectionally solidifying molten silicon in a crucible upward from the bottom of the crucible, the molten silicon is unidirectionally solidified to obtain the polycrystalline silicon ingot under such conditions that, while the temperature Tm detected when the silicon temperature agrees with the melting point of the silicon, at a position in the vicinity of the center of the under surface of the crucible falls from (Tm-20)°C to (Tm-60)°C, there is a period during which the temperature falls at a temperature changing rate of 1-10°C/hr. |
