Low defect density, ideal oxygen precipitating silicon

摘要

A single crystal silicon wafer which, during the heat treatment cycles of essentially any electronic device manufacturing process, will form an ideal, non-uniform depth distribution of oxygen precipitates. The wafer is characterized in that it has a non-uniform distribution of crystal lattice vacancies, the concentration of vacancies in the bulk layer being greater than the concentration of vacancies in the surface layer and the vacancies having a concentration profile in which the peak density of the vacancies is at or near a central plane with the concentration generally decreasing from the position of peak density in the direction of a front surface of the wafer. The wafer is further characterized in that it has a first axially symmetric region which is substantially free of agglomerated intrinsic point defects. A process for making such a wafer is also disclosed.