Patent ID: 6984264

Claim:
A single crystal pulling device comprising: a cylindrical pulling furnace; a crucible disposed in the pulling furnace so as to melt a single crystal material for a semiconductor poured therein; a cylindrical vacuum vessel coaxially disposed around an outer periphery of the pulling furnace; and a superconducting element disposed in the vacuum vessel so as to generate magnetic field which is applied to the single crystal material to thereby suppress a convection of the melted single-crystal material in the crucible, wherein said superconducting element comprises at least two pairs of superconducting coils arranged on a same horizontal plane of the cylindrical vacuum vessel, wherein the at least two pairs of superconducting coils are Helmholtz coils that generate a magnetic field along a same transverse direction, and each of the paired superconducting coils includes coils set so as to oppose to each other with respect to a central axis of the cylindrical vacuum vessel so that one coil of one pair of coils and one coil of another pair of coils adjacent to the first mentioned one pair of coils constitutes a set angle, directing towards the inside of the cylindrical vessel, in a range of 100° to 130°.