| Sodium bismuth tungstate single crystal (NBW) is a scintillating crystal with good performance, and the excellent feature of the crystal such as little decay constant, more radiation hardness, high density, small radiation length, no deliquescence , good machining property is probed. It's home and overseas developing status and future applications.In this paper, NBW is grown by using Czochralski Method with medium- frequency induction heating, and we study the luminescence mechanism of the crystal. The experiment is done for improving the crystal quality and radiation hardness property. The optimal growth condition is presented as follows: the axis temperature of the center of solid-liquid interface is 0.8 ℃/ mm. Temperature gradient in diameter should be little, pulling rate 2～4 mm/h, rotating rate 12-18 r/min, cooling rate 35℃ /h, and we have got the high quality NBW single crystal with Φ 40×50 mm. The X-ray diffraction (XRD) spectra shows that the NBW single crystal belongs to cubic system with the space group of I41/a, the unit cellparameters of NBW crystal are a = b = 5.30 (?), c = 11.58 (?). The transmission spectra indicates that the NBW crystal has a strong anti-radiation damaging feature. Its emission peak, in the range of green light wave band, is about 540 nm, which can match silicon photoelectric diode. Finally, we test the capability of the single scintillating crystal, and discuss the reason about the crystal painting and the anti-radiation influence owing to the anneal. It is found that the main reasons about NBW crystal painting are impure raw materials and oxygen vacancy defects. The best two methods which can improve the property of NBW crystal are heightening the purity of raw materials and doing the anneal with high temperature and abundant oxygen.
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