| 摘要 |
PROBLEM TO BE SOLVED: To provide an orientation flat position determination method and an orientation flat position determination device that can easily and securely determine an orientation flat position.SOLUTION: There is provided an orientation flat position determination method for sapphire crystal, the orientation flat position determination method including the steps of: making X rays incident on a side face of columnar sapphire crystal including a "c" axis as its center axis; detecting generating diffracted rays and specifying the position of a crystal plane of the sapphire crystal which is symmetrical by three rotations on the "c" axis and the position of an "a" plane so as to specify a "-a" plane; and determining the specified position of the "-a" plane as an orientation flat position. The crystal plane which is symmetrical by three rotations on the "c" axis is thus used to discriminate between a "+a" plane and the "-a" plane with respect to the "a" plane as a crystal plane of symmetry by six rotations, and the orientation flat position specified with the "-a" plane can be easily and securely determined. |
