Patent ID: 9123671
Filing Date: 2015-09-01
Classification: H01L

Abstract:
1. A method, comprising: receiving a silicon wafer; implanting oxygen to the silicon wafer through one or more implantation processes, thereby transforming the silicon wafer into an oxygen-rich silicon wafer, wherein the oxygen-rich silicon wafer has an oxygen concentration greater than about 15 parts-per-million-atoms; forming a zone in the oxygen-rich silicon wafer, by subjecting the oxygen-rich silicon wafer to a first temperature high enough to cause oxygen out-diffusion and for a first duration, the zone being substantially depleted of oxygen; causing a nucleation process to take place, at a silicon atom forming site in the oxygen-rich silicon wafer, by subjecting the oxygen-rich silicon wafer to a second temperature less than the first temperature and for a second duration greater than the first duration, to form oxygen nuclei in a region of the oxygen-rich silicon wafer outside the zone, wherein after forming the zone in the oxygen-rich silicon wafer and before causing the nucleation process to take place, cooling the oxygen-rich silicon wafer to a room temperature; and growing the oxygen nuclei into defects, by subjecting the oxygen-rich silicon wafer to a third temperature greater than the second temperature but less than the first temperature and for a third duration greater than the second duration.