Internal gettering for germanium-doped Czochralski silicon: Treated by rapid-thermal-anneal based processing simulation

摘要

Intrinsic gettering (IG) in germanium-doped Czochralski (Cz) silicon wafer has been investigated through a processing simulation of dynamic random access memory fabrication involved with rapid-thermal-anneal (RTA). Compared with that of conventional Cz silicon, both the good quality defect-free denuded zone (DZ) with a slightly narrower width and the gettering region with a slightly higher density of bulk micro-defects (BMDs) could be generated in germanium-doped Cz (GCz) silicon during the device fabrication. These phenomena were interpreted through the generation of denser oxygen precipitates in GCz silicon than Cz silicon, which were considered to be ascribed to the enhancement of precipitate nucle-ation by the germanium doping. It is therefore believed that the germanium doping could improve the IG capability for Cz silicon wafer.