| With the development of VLSI (Very Large Scale Integration) and ULSI (Ultra Large Scale Integration), RTP (Rapid Thermal Process), which consumes less time and less energy than classical thermal treatments, have been widely employed in semiconductor manufacturing. However, the most importance is that RTP is applied for defects engineering of silicon material. It is generally believed the RTF leads to the injection of additional vacancies into silicon wafer, and then a so-called magic denuded zone (MDZ) in the near-surface region of CZ silicon wafer was formed by controlling the vacancy distribution. Because of this, the behavior of impurities and defects in silicon during the RT P become a new research focus.Although the diffusion of nitrogen and oxygen in silicon has been intensely studied respectively, the mechanism on in-diffusion of nitrogen and oxygen into silicon during RT P is unavailable. This research will provide theoretic direction for RTP application to defects engineering. Also, the NCZ (nitrogen doped silicon), which is my laboratory research characteristic, is research focus at present because it has strong mechanical strength and advantage intrinsic gettering property. Eliminating the nitrogen-oxygen complexes by RTP has not only creativity, but also have a significant practice sense.In this paper, the relationship of the thermal donor with point defects was investigated by injection of different concentration and distribution vacancy via 1250 癈 , RTP preannealing in different gases (N2 O2, Ar). The influence of RTF preannealing on generation at 450 癈 and annihilation at 650癈 of thermal donors (TD's) was not detected. The experimental results indicate that the formation of TDs has not related to point defects and has an excellent agreement with chain-model of TDs (without point thermal donor model).On the other hand, to research the in-diffusion behavior of nitrogen and oxygen into silicon during high temperature RTP, the CZ silicon and FZ silicon were used respectively. CZ silicon and FZ silicon preannealed by high temperature RTP in different atmosphere (N2, O2, Ar) were treated at range of 550~1050癈 for one hour to detect the change in resistivity by four probe method. We found that the CZ silicon wafers preannealed by RTP in nitrogen atmosphere are significantly characteristic of NCZ silicon wafer, that is, the N-O complexes related STDs are also generated in theCZ wafer subjected to RTF in Na and subsequent proper heat treatments. The fact verified that the nitrogen was diffused into silicon wafer during RTF in nitrogen atmosphere. In-diffusion of nitrogen during RTF was affected by RTF temperature, time, and thickness of wafer etc.. It was estimated that the diffusion coefficient of nitrogen in silicon at 1250癈 was 4.6 X 10"5 cm2/s. It is concerned that during the RTF at high temperature nitrogen atoms and vacancies may react to generate NiV2 complexes that could diffuse very fast in silicon. In this experiment, in-diffusion of oxygen during RTF was not detected.Also, annihilation of thermal donor and nitrogen- oxygen complexes by RTF was investigated. In this experiment, thermal donor in CZ silicon generated by 450癈 annealing for 32 hours was eliminated by RTF at range of 600~700癈 for different time. Furthermore, the permit temperature and time for annihilation of thermal donor by RTF was found. In the same way, the NCZ silicon with nitrogen-oxygen complexes was annealed by RTF at range of 750-950 癈 for different time to detect the change in resistivity. We found that nitrogen-oxygen complexes were annihilated with less time and lower temperature than conventional annealing method. The mechanism was discussed in this paper.
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