| 摘要 |
PROBLEM TO BE SOLVED: To provide an apparatus for producing a semiconducting single crystal, enabling the easy controlling of the temperature inclination of a single crystal pulled up by CZ method and capable of producing a silicon single crystal having high quality especially by suppressing the occurrence of as-grown defect. SOLUTION: This apparatus is provided with the first heat-insulating tube 8 surrounding a single crystal 12 which is being pulled up, and the second heat-insulating tube 10 placed inside the first heat-insulating tube 8 and surrounding the single crystal 12. The second heat-insulating tube 10 is fixed by bringing a supporting member 11 attached on the outer peripheral surface of the second heat-insulating tube 10 to contact with the first heat-insulating tube 10. By means of the first heat insulating tube 8 to stimulate shape stabilization, the single crystal 12 is quickly cooled near the solid- liquid boundary surface. Further, owing to the second heat-insulating tube 10, the temperature inclination of the single crystal 12, while it passes in the region of 1200-1000 deg.C, becomes small to reduce the density of crystal defects. Thus, a single crystal excellent in oxide-film breakdown strength is obtained. By changing the supporting member 11, the fixing position of the second heat-insulating tube 10 can be adjusted in the vertical direction so that a desired site of the single crystal can be annealed. |
