Patent ID: 7780783

Claim:
A method for producing a single crystal comprising: heating a polycrystalline silicon raw material held in a crucible to form a silicon melt; and growing a silicon single crystal by pulling it from said silicon melt accompanied with rotation, wherein: a cusp magnetic field is generated so that a vertical position of a magnetic field neutral plane is within a range of from 30 mm to 120 mm below a solid-liquid interface, and a horizontal component of the magnetic flux density at a wall position of said crucible is within the range of from 0.02 to 0.09 T; and said silicon single crystal is pulled with said crucible being rotated at a rotation speed less than or equal to 3 min −1 , and with said silicon single crystal being rotated in a direction opposite to a rotation direction of said crucible at a rotation speed greater than or equal to 12 min −1 ; said silicon single crystal is grown by pulling accompanied with applying to said silicon melt a cusp magnetic field a neutral plane of which is symmetric around a rotation axis of said silicon single crystal and is curved in an upward direction; and said cusp magnetic field is generated so that a difference between a vertical position of said magnetic field neutral plane upon said rotation axis and a vertical position of said magnetic field neutral plane at the wall position of said crucible is greater than or equal to 15 mm.