| 摘要 |
Provided is a sapphire single crystal core characterized by having an r-axis axial direction, having a length of at least 200 mm, having a diameter of at least 150 mm, and containing no bubbles. Also provided is a method for producing the sapphire single crystal core, characterized by: including a step in which a sapphire single crystal is grown in the r-axis direction by the Czochraski method and a sapphire ingot is obtained and a step in which a core is cut out of the sapphire ingot; and, during the formation of a shoulder section of the ingot by the Czochraski method, the speed of the formation of the shoulder section being controlled such that the growth direction length is no more than 10 mm for an area in the shoulder section that is an area having an angle of 10-30° relative to the horizontal surface. |
