| Semiconductor silicon is the most fundamental material for the microelectronic industry. Along with the fast development of ultra large scale integrated circuit (ULSI), the manipulation of impurities and defects in the CZ silicon crystal has been increasingly stringent. In this thesis, light germanium-doping has been employed to engineer the grown-in defects in CZ silicon. By means of FTIR (Fourier transfer inferred spectrum), TEM (Transmission electronic microscopy), SRP (Spreading Resistance), and SSIS (Laser particle counter), the defects of oxygen precipitate and void in CZ silicon have been intensively investigated.The effect of Ge-doping on the formation of grown-in oxygen precipitates was investigated. It was found that the Ge-doping could increase the onset temperature for the formation of oxygen precipitates during CZ silicon growth. The amount of grown-in oxygen precipitates was found to be increased by Ge-doping and moreover, the size profile of grown-in oxygen precipitates was also modified by Ge-doping. Furthermore, it was verified that the Ge-doping could significantly facilitate oxygen precipitation occurring in the post growth heat-treatments at temperatures not higher than 1150℃.Oxygen precipitation in CZ and GCZ silicon during the prolonged anneals at 800 ℃ and 1000℃ for up to 225 h was intensively investigated. It was found that the Ge-doping significantly enhanced oxygen precipitation in terms of the amount of precipitated oxygen atoms and the density of oxygen precipitates. Moreover, the TEM observation revealed that the morphology and size of oxygen precipitates were modified by Ge-doping. On the other hand, the dissolution behavior of oxygen precipitates formed by 800℃/1000℃, 225 h anneals in the CZ and GCZ silicon was investigated by high temperature anneal. It was indicated that the oxygen precipitates in GCZ silicon were much more readily dissolved by high temperature anneal compared to those in CZ silicon, the reason for which is that, on one hand, the Ge-doping resulted in higher density and smaller sized oxygen precipitates and therefore larger overall surface of oxygen precipitates contributing to escape of oxygen atoms; on the other hand, as mentioned above, the oxygen concentration in the GCZ silicon was much lower than that in the CZ silicon after the same precipitation anneal, thus the driving force for the dissolution of oxygen precipitates at elevated temperature anneal for the GCZ silicon was larger silicon than for the CZ silicon.The issue of intrinsic gettering (IG) of GCZ silicon wafer was addressed. It was found that the oxygen precipitates- denuded zone and bulk microdefect region could besimultaneously formed within the GCZ silicon wafer by just one single-step high temperature anneal, which was not the case for the conventional CZ silicon. It is belived that the Ge-doping enhanced oxygen out-diffusion in the proximity of wafer surface and oxygen precipitation in the wafer bulk can be contributed to the simultaneous formation of DZ and BMDs region during the single-step high temperature anneal.The influence of Ge-doping on the formation of oxygen related donors were investigated. The formation of thermal donors (TDs) was greatly suppressed due to the sluggish aggregation of oxygen atoms at 450 because considerable amount of oxygen atoms were previously combined with germanium and vacancy to form stable complexes. While, the formation of new donors (NDs) was enhanced due to the fact that the complexes of Ge-O-V could act as the nucleation centers for the formation of relatively larger oxygen aggregates which were electrically active.The formation of crystal originated particles (COPs) and annihilation of COPs by hydrogen annealing at high temperature in GCZ silicon were studied. It was experimentally found that the Ge-doping facilitated the formation of denser COPs in smaller size, moreover, the COPs in GCZ silicon could be much more significantly annihilated by hydrogen annealing at high temperature in comparison with those in the CZ silicon. It is b...
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