Intrinsic gettering Based on rapid thermal annealing in germanium-doped Czochralski silicon

Abstract

The intrinsic gettering (IG) effects under different thermal processes involved with rapid thermal annealing (RTA) in Czochralski (CZ) silicon wafers with germanium doping have been investigated. It has been shown that both good quality denuded zones and high-density bulk microdefect regions could be generated in germanium-doped CZ (GCZ) silicon wafers through thermal cycles of RTA treatments plus either low-high temperature two-step annealing or high temperature single-step annealing. Moreover, more oxygen precipitation was formed in GCZ silicon wafers in comparison with conventional CZ silicon wafers, indicating the enhancement of IG capability for CZ silicon wafers by the germanium doping. The phenomena have been considered to be ascribed to the increase of vacancy concentration associated with the presence of germanium, which results in the generation of Ge-V-related complexes in GCZ silicon wafers during RTA treatments.