Single crystal pulling apparatus and method for pulling single crystal

A single crystal pulling apparatus comprising:

• a pulling furnace in which a heating heater and a crucible containing a molten semiconductor raw material are arranged and has a central axis;
• and a magnetic field generating apparatus provided around the pulling furnace and having superconducting coils, for applying a horizontal magnetic field to the molten semiconductor raw material by energizing the superconducting coils to suppress convection of the molten semiconductor raw material in the crucible,
• wherein the superconducting coils of the magnetic field generating apparatus are saddle-shaped and are curved along an outer shape of the pulling furnace, the saddle-shaped superconducting coils having a vertical width shorter than a horizontal width, and two pairs of the saddle-shaped superconducting coils are arranged around the pulling furnace with the saddle-shaped superconducting coils of each pair arranged facing each other,
• when an axis passing through the centers of a pair of superconducting coils arranged facing each other is defined as a coil axis,
• two coil axes of the two pairs of superconducting coils are included in the same horizontal plane, and
• when a magnetic force line direction on the central axis of the pulling furnace in the horizontal plane is defined as a X-axis, and a direction perpendicular to the X-axis in the horizontal plane is defined as a Y-axis, a center angle α between the two coil axes sandwiching the X-axis is 90 degrees or less and an inter-coil angle β between adjacent superconducting coils sandwiching the Y-axis is 20 degrees or less.