Effect Of Electron Irradiation On The Properties Of Monocrystalline Silicon

With the rapid development of integrated circuits, the requirements on silicon materials become increasingly stringent. It is the most important issue for the development of silicon materials to control and elimination of microdefects in monocrystalline silicon. In this paper, the influences of electron irradiation on the electrics performance and internal gettering (IG) in monocrystalline silicon under various annealing processing conditions were investigated.Defects of VO,VO2,Ci-Oi and Oi2 were observed in silicon crystal irradiated by electron. These defects produced by electron irradiation results in degradation of electrical parameters of silicon, which arises mainly from the introduction of defects with deep levels in the energy bandgap. We found that the concentration of VO defect is proportional to power 0.75 of electron-dose and power 0.8 in high oxygen and low oxygen specimens, respectively. It has been found that there is a clearly pronounced shoulder at about 826 cm-1 on the low-energy side of the band. The relative intensity of the shoulder was found to be dependent on the influence of electrons. Complete recovery of the concentration and mobility of charge carriers in irradiated materials takes place around 700℃. The stability of the VO2 decreased with annealing temperature. The VO2* defect existed around 450℃. VO2 has an LVM frequency at 889 cm-1, we have tentatively correlated the second peak at 884 cm-1with a [VO2+V] structure.High-quality denuded zone (DZ) and high density bulk micro defects (BMDs) could be formed in electron irradiated CZ-Si wafer by RTP pre-annealing. DZ width decreased with RTP temperature and cooling rate increasing, contrarily the density of BMDs increased. Meanwhile, oxygen precipitates concentration in irradiated CZ-Si wafer subjected to RTP pre-annealing decreased with RTP temperature and cooling rate. In comparison with the RTP under Ar ambient, the RTP under N2 ambient could lead to higher density of oxygen precipitates generated in electron irradiation Czochralski silicon.