| With the rapid development of ultra large-scale integrated circuits, the requirements on silicon materials become increasingly stringent. The control and elimination of microdefects in monocrystalline silicon is the most important issue for the development of silicon materials. Defects induced by high-energy particles can control and use the as-grown defects in silicon. Thus, it is important to investigate the effects of high-energy particles irradiation in monocrystalline silicon. In this dissertation, based on the irradiation by fast neutron and electron, the irradiated defects behavior, the oxygen precipitation behavior and the IG process have been intensively investigated. Listed below are the most important results achieved in this work.(1) The influence of fast neutron irradiation on monocrystalline silicon has been systematically investigated. It is found that the influence of fast neutron irradiation on the electronic properties of monocrystalline silicon is obviously. There are many accepted levels induced by irradiation after annealing at 450℃. The influence of irradiation on the electronic properties begins disappearance when annealing at 650℃. The formation of thermal donors is inhibited by pre-annealing in irradiation silicon.(2) After irradiation, the concentration of interstitial oxygen decrease. Annealing at 200℃, VO complex begin to transform to V2O or O-V-O. O-V-O is a metastable structure of VO2. It will transform to VO2 when annealed at higher temperature. The divacancy connect with each other when annealed at low temperature in low oxygen concentration silicon. And it transforms to V3O by trap VO in high oxygen concentration silicon. The concentration of interstitial oxygen decreases after annealing at 1100℃. It decreases to the lowest when the irradiation dose increases to 5×1017 cm2. The spherical oxygen precipitates, platelet oxygen precipitates and octahedron oxygen precipitates appear when annealing at 1100℃. The rapid thermal process (RTP) cannot change the process of oxygen precipitated in irradiation monocrystalline silicon, but it is useful to the formation of denuded zone (DZ). The cooling rate of RTP influence the oxygen precipitates and the higher cooling rate is good condition for the formation of oxygen precipitates.(3) The influence of fast neutron irradiation on nitrogen doped Czochralski silicon (NCZ-Si) has also been systematically investigated. It is found that DZ formed easily in fast neutron irradiation NCZ-Si by process of RTP. It is the best condition for DZ when annealing at 1100℃/10h. The concentration of interstitial oxygen in NCZ-Si which irradiated by fast neutron increases with the irradiation dose when RTP at high temperature. The formation of N-O complex was influenced by the cooling rate of RTP. It is easily formed under high cooling rate.Finally, the influence of electron irradiation on monocrystalline silicon has been investigated. It is found that influence of electron irradiation on electrical property and DZ of monocrystalline is obviously. The concentration of interstitial oxygen and minority carrier lifetime decreases with the irradiation dose. On the other hand, the resistivity increases. The VO2 complex begin to form when annealing at 400℃. The DZ can be formed after annealing by RTP and one step annealing at high temperature. The temperature of RTP and its cooling rate are important for the size of DZ.
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