Patent ID: 8026145
Filing Date: 2011-09-27
Classification: C30B,H01L

Abstract:
1. A process for heat-treating a single crystal silicon wafer sliced from a single crystal silicon ingot grown by the Czochralski method to influence the precipitation behavior of oxygen in the single crystal silicon wafer in a subsequent thermal processing step, the single crystal silicon wafer having a front surface, a back surface, a central plane between the front and back surfaces, a front surface layer which comprises the region of a wafer between the front surface and a depth, D 1 , measured from the front surface and toward the central plane, a bulk layer which comprises the region of the wafer between the central plane and front surface layer, is doped with arsenic or phosphorous, and has a resistivity of less than about 5 mΩ-cm, the process comprising: heat-treating the single crystal silicon wafer in an atmosphere comprising a nitrogen-containing gas to increase a density of crystal lattice vacancies in the wafer bulk; and cooling the heat-treated single crystal silicon wafer such that the wafer bulk is supersaturated with crystal lattice vacancies.