摘要 |
A single-crystal pulling device includes vertically tilted magnetic coils between the walls of a cooling vessel. The inside and outside walls of the cooling vessel are coaxially aligned about a central axis. The inside wall of the cooling vessel is coaxially disposed around a cylindrical crucible that holds molten semiconductor material. A mid line passes through the middle point of a first coil, the central axis and the middle point of a second coil. The first coil is wound in a first plane, and the second coil is wound in a second plane. The first plane and the second plane both intersect the central axis at the same point. The first plane intersects the central axis at an angle between 5 and 15 degrees. In one embodiment, the first plane intersects the central axis below the crucible. In another embodiment, the first plane intersects the central axis above the crucible. |