Semiconductor crystal growth via variable melt rotation.

摘要

An improvement in the method and apparatus for growing a semiconductor crystal by the Czochralski technique comprising the steps of applying a rotating transverse magnetic field to molten semiconductor material (12) held in a crucible (10) during the seed crystal pulling and crystal (22) formation step, to cause the molten material (12) to rotate within the crucible, and simultaneously increasing the rotational velocity of the magnetic field during this crystal formation as a function of the length of the crystal (22) pulled from said molten material to thereby vary the rotation rate of the molten material. These steps result in the uniform axial distribution of oxygen in the crystal.