Patent ID: 8172941

Claim:
A method for producing semiconductor wafers of silicon having a diameter of 300 mm or more, comprising pulling of a single crystal from a melt contained in a crucible having side walls and a bottom, and slicing semiconductor wafers from the pulled single crystal, comprising growing a single crystal and delivering heat to a center of the growing single crystal at a boundary with the melt during the pulling of the single crystal, and applying a CUSP magnetic field to the melt such that a neutral surface of the CUSP magnetic field intersects a pulling axis of the single crystal at a distance of at least +50 mm above a surface of the melt; providing a lateral heat source surrounding the crucible, an annular heat source above the melt surface surrounding the single crystal, a static heat source which is arranged statically below the crucible, and a mobile heat source at the crucible bottom which is raised with the crucible while the single crystal is being pulled; and dividing a heating power between the heat sources.