| 摘要 |
PROBLEM TO BE SOLVED: To provide a unit capable of producing a large diameter and long length high quality single crystal stably and collecting a wafer having less Grown-in defects such as a dislocated cluster or an infrared rays-scattering body. SOLUTION: This production unit of the silicon single crystal is provided by installing a cooling member surrounding the single crystal and having an inner circumferential surface which has the same axis as the pulling out shaft, and a heat-insulation material at the outside of the outer surface and the lower side of the lower end surface of the cooling member. By setting the diameter of the pulled out single crystal as D, the cooling member has 1.20D-2.50D inner circumferential diameter, <=0.25D length and 0.30D-0.85D distance from the surface of molten liquid to the lower end surface of the cooling member, and the heat insulation material at the lower side of the lower end surface of the cooling member has a smaller inner diameter than the inner diameter of the lower end part of the cooling member. |
