Novel glittering crystal LaBr3Ce3+ crucible-lowering method growth process

Abstract

The present invention discloses a growth craft of crucible descent method of neotype scintillating crystal LaBr3:Ce3+, which belongs to the domain of crystal growth. Take LaBr3.7H2O and CeBr3.7H2O as the initial raw material, and prepare anhydrous bromide LaBr3 and CeBr3 through the processing of halogenation roasting anhydration. Prepare LaBr3:Ce3+ batch according to suitable CeBr3 doping density, and mix into few active carbon powders as the deoxidizer. Fill crystallons and raw materials using special platinum crucible, and put crucible into crystal growth stove after solder seal it. Control furnace temperature between 850 Deg C and 900 Deg C. Adjust the position of crucible to make welding raw materials and crystallons, and it will form the solid liquid interface whose temperature gradient is between 20 Deg C/centimeter and 50 Deg C/centimeter. Carry on the crucible decline crystal growth at the speed of 0.3-3millimeter/hour, and it can be grown high quality and integrity LaBr3:Ce3+ single crystal. The craft has solved the key technology problems of anhydrous raw material preparation, melt mass oxidation and volatilization and so on, and LaBr3:Ce3+ single crystal can be mass grown in the condition of non-vacuum airtight crucible.

Description

technical field [0001] The invention belongs to the technical field of single crystal growth. LaBr 3 : Ce 3+ Single crystal is a kind of scintillation crystal material discovered in recent years with excellent luminous properties. It has quite high luminous efficiency, high energy resolution, and short decay time, so it is considered by the material science community to be a scintillation crystal with great application value. , which is expected to be applied in the field of radiation detection technology mainly based on nuclear medical imaging. High-quality large-size LaBr that meets practical needs can be grown by adopting the technology of the present invention. 3 : Ce 3+ single crystal. Background technique [0002] In recent years, the rapid development of nuclear medical imaging technology has greatly promoted the research and development of inorganic scintillation crystals. The main performance requirements of medical scintillation crystals are: high luminous eff...

AI Technical Summary

Problems solved by technology

Due to the physical properties of rare earth halides, LaBr 3 : Ce 3+ The inherent key technical problem of crystal growth is: (1) usually commercially available reagent is the LaBr that contains water of crystallization 3 .7H 2 O and CeBr 3 .7H 2 O, and anhydrous bromide LaBr 3 and CeBr 3 It is easy to absorb moisture in the air; during the crystal growth process, hydrolyzed bromide is prone to hydrolysis to generate bromide oxides and oxides, resulting in optical scattering or even devitrification of the crystal. The preparation of high-purity anhydrous bromide is the growth quality Preconditions for single crystals; (2) LaBr 3 : Ce 3+ The crystal is a consistent molten rare earth bromide, which is stable at room temperature, but its melt is easily oxidized and volatilized at the crystal growth temperature. How to prevent the oxidation and volatilization of the melt has become a breakthrough in its crystal growth process. The key issue

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