Abstract: Single crystal semiconductor wafers comprise oxygen and an n-type dopant, and are produced by a process comprising providing a silicon melt containing n-type dopant in a quartz crucible, the melt having an initial height hM; heating the melt from the side by selectively supplying heat to an upper volume of the melt having an initial height hm, wherein hm is smaller than hM; pulling a single crystal of silicon from the melt by the CZ method with a pulling velocity V; heating the melt from above in the region of a phase boundary between the growing single crystal and the melt; heating the melt from above in the region of a surface of the melt; subjecting the melt to a magnetic field; counterdoping the melt with p-type dopant; and separating the semiconductor wafer of single-crystal silicon from the single crystal. An apparatus for accomplishing the process is also disclosed.

Abstract: Single crystal semiconductor wafers comprise oxygen and an n-type dopant, and are produced by a process comprising providing a silicon melt containing n-type dopant in a quartz crucible, the melt having an initial height hM; heating the melt from the side by selectively supplying heat to an upper volume of the melt having an initial height hm, wherein hm is smaller than hM; pulling a single crystal of silicon from the melt by the CZ method with a pulling velocity V; heating the melt from above in the region of a phase boundary between the growing single crystal and the melt; heating the melt from above in the region of a surface of the melt; subjecting the melt to a magnetic field; counterdoping the melt with p-type dopant; and separating the semiconductor wafer of single-crystal silicon from the single crystal. An apparatus for accomplishing the process is also disclosed.

Abstract: A ring-shaped resistance heater for supplying heat to a growing single crystal, contains an upper and a lower ring, which are electrically conductively connected by means of a loop adjacent to a ring gap of one ring, such that the flow direction of electric current which is conducted through the rings is opposite in the rings; connecting elements which hold the upper and lower rings together in a spaced apart relationship; and current leads for conducting electric current through the upper and lower rings.

Abstract: Silicon semiconductor wafers are produced by pulling a single crystal at a seed crystal from a melt heated in a crucible; supplying heat to the center of the crucible bottom with a heating power which, in the course of the growth of a cylindrical section of the single crystal, is increased at least once to not less than 2 kW and is then decreased again; and slicing semiconductor wafers from the pulled single crystal.

Abstract: A ring-shaped resistance heater for supplying heat to a growing single crystal, comprising: an upper and a lower ring, which are electrically conductively connected by means of a loop adjacent to a ring gap of the lower ring, such that the flow direction of electric current which is conducted through the rings is opposite in the rings; connecting elements which hold the upper and lower rings together at a distance; and current leads for conducting electric current through the upper and lower rings.

Abstract: Silicon semiconductor wafers are produced by pulling a single crystal at a seed crystal from a melt heated in a crucible; supplying heat to the center of the crucible bottom with a heating power which, in the course of the growth of a cylindrical section of the single crystal, is increased at least once to not less than 2 kW and is then decreased again; and slicing semiconductor wafers from the pulled single crystal.