| 简介 |
FIELD : crystal growth.
SUBSTANCE : invention relates to the technology of growing scintillation single crystals based on cerium bromide with the general formula CeBr3 with a 100% content of scintillating ion Ce3+ by horizontal directional crystallization (HDC) and can be used in the manufacture of detector elements and spectrometers sensitive to gamma, X-ray radiation and other types of ionizing radiation. A method for producing a crystalline scintillator based on self-activated rare earth halide CeBr3 involves melting the initial charge and growing crystals in quartz ampoules or in a graphite boat in HDC installation by moving them through the heating zone, while ampoules with installed CeBr3 crystal priming inside a pumped glove box are loaded with anhydrous crystals of the starting material with a purity of 99.99%, heated to a temperature of more than 100°C for 2 hours, pumped out up to 10-3 mm Hg and they are sealed with an oxygen-propane burner, then the ampoules are installed in a growth unit, after creating a vacuum in the unit up to 10-3 mm Hg they are heated until the charge melts, kept in a growth unit for 2-4 hours until an equilibrium state is established in the melt, a single crystal is grown by creating a gradient temperature section in the ampoule with horizontal stretching from the heating zone to the cooling zone at a speed of 5 mm/h, after which the ampoule is slowly cooled to room temperature to anneal the grown crystal, and when grown in a graphite boat, the starting material with CeBr3 seed is installed in a growth unit, which is then evacuated to 10-3 mm Hg, dried at a temperature of 200°C for 24 hours, after that, inert gas Ar and Br are injected in a mixture with the addition of brominating agent tetrabromomethane CBr4 and dehydrogenating agent cadmium bromide CdBr2 to an excess pressure of 1.06 atm, the charge is melted at a temperature of 732°C, the temperature is raised by 50°C and the crystal growing process is carried out by the method for horizontal directional crystallization at a horizontal boat pulling speed of 5 mm/h, after the crystallization process is completed, the grown crystal is annealed at a slow temperature decrease of ~ 10-15°/h.
EFFECT : production of materials of CeBr3 stoichiometric composition with a purity of 99.99% in the form of single-crystal samples or polycrystals.
1 cl, 2 dwg, 3 ex |
客服热线：
手机版
二维码
