Provided is a method of fabricating a semiconductor device. The method includes: receiving a silicon wafer that contains oxygen; forming a zone in the silicon wafer, the zone being substantially depleted of oxygen; causing a nucleation process to take place in the silicon wafer to form oxygen nuclei in a region of the silicon wafer outside the zone; and growing the oxygen nuclei into defects. Also provided is an apparatus that includes a silicon wafer. The silicon wafer includes: a first portion that is substantially free of oxygen, the first portion being disposed near a surface of the silicon wafer; and a second portion that contains oxygen; wherein the second portion is at least partially surrounded by the first portion.