Bridgman-stockbarge process for growing scintillation crystal LaCl3:Ce3+

Abstract

The present invention is Bridgman-Stockbarge process of growing scintillation crystal LaCl3:Ce3+, and belongs to the field of monocrystal growing technology. The initial material LaCl3 .7H2O and CeCl3 .7H2O are first prepared into anhydrous chlorides LaCl3 and CeCl3 through chlorination, roasting and dewatering; and compounded material LaCl3:Ce3+ with proper CeCl3 doping concentration and small amount of active carbon powder blended as deoxidizer is then prepared. After filling the seed crystal and material are set inside platinum crucible and the crucible is sealed up, the crucible is set in crystal growing furnace at 920-980 deg.c for soldering the material to the seed crystal and forming solid-liquid interface of temperature gradient of 20-50 deg.c / cm, and the crucible is then fallen at the speed of 0.3-3 mm / hr to grow excellent LaCl3:Ce3+ monocrystal. The process is suitable for mass production of LaCl3:Ce3+ monocrystal.

Description

technical field [0001] The invention belongs to the technical field of single crystal growth. LaCl 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 and large-size LaCl 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 ...

AI Technical Summary

Problems solved by technology

[0004] Due to the physical properties of rare earth halides, LaCl 3 : Ce 3+ The inherent key technical problems of crystal growth are: (1) usually commercially available reagents are LaCl containing water of crystallization 3 .7H 2 O and CeCl 3 .7H 2 O, and anhydrous chloride LaCl 3 and CeCl 3 It is easy to absorb moisture in the air; during the crystal growth process, hydrolyzed chlorides are prone to hydrolysis to generate oxychlorides and oxides, resulting in optical scattering and even devitrification of the crystals. The preparation of high-purity anhydrous chlorides is a good way to grow The primary technical conditions for single crystal; (2) LaCl 3 : Ce 3+ The crystal is consistent molten rare earth chloride, 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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