Flux technology growth apparatus and method of rare earth doped orthophosphate crystals

Abstract

The invention belongs to the technical field of monocrystal growth, relates to an apparatus suitable for flux technology monocrystal growth, and especially relates to a flux technology growth apparatus and a method of rare earth doped orthophosphate crystals. The method comprises the following steps: mixing lead oxide with lead fluoride, compacting the lead oxide with lead fluoride to form a cylindrical block structure in order to obtain a flux, disposing a YbPO4 and YPO4 mixture in the bottom of an inner wall, compacting the mixture, and disposing the flux on the mixture; and screw-capping an upper cover on an outer wall, sealing the upper cover, disposing the growth apparatus in a heating furnace, adjusting the temperature of the heating furnace, heating to 800DEG C, and sequentially cooling to 750DEG C, 700DEG C, 600DEG C, 500DEG C and room temperature to end crystal growth. The apparatus adopted in the invention has the advantages of simple structure, convenient operation, low cost, less energy consumption, reduction of the energy loss due to reduction of the crystal growth temperature to 400DEG C, high dimensions and high quality of grown crystals, reduction of discharge of toxic substances, and environmental protection.

Description

Technical field: [0001] The invention belongs to the technical field of single crystal growth, and relates to a device suitable for single crystal growth by a flux method, in particular to a rare earth-doped orthophosphate crystal growth device and method by a flux method. Background technique: [0002] At present, in the crystal growth of the flux method, the platinum crucible used is generally open or covered, and the growth system is open or semi-open. During the crystal growth process, high temperature will cause volatilization of substances. Lead-containing fluxes have high solubility to most materials and a good temperature coefficient of solubility. They are a type of flux commonly used in crystal growth by flux method. Taking the most common lead oxide as an example, its temperature of several hundred degrees Celsius It will volatilize at high temperature, and there will be a large saturated vapor pressure at 1200 degrees Celsius. The volatilization of lead compounds...

AI Technical Summary

Problems solved by technology

Lead-containing fluxes have high solubility to most materials and a good temperature coefficient of solubility. They are a type of flux commonly used in crystal growth by flux method. Taking the most common lead oxide as an example, its temperature of several hundred degrees Celsius It will volatilize at high temperature, and there will be a large saturated vapor pressure at 1200 degrees Celsius. The volatilization of lead compounds into the air will pollute the atmosphere and damage the health of experimenters

Therefore, researchers continue to explore new lead-free flux systems, but have not yet found a new flux system with comparable performance to lead-containing fluxes. Therefore, the transformation of experimental equipment to solve the adverse effects of lead-containing fluxes will affect crystal growth and The exploration of new crystals is of great significance

[0003] Commonly used rare earth-doped orthophosphate flux systems are lead pyrophosphate, tungstate and molybdate systems, among which tungstate and molybdate have a relatively complex growth system, so that the grown crystal size and quality are not as good as Lead pyrophosphate system, but the melting point of the lead pyrophosphate system is about 900°C, and the phosphorus and lead compounds in the system all volatilize to varying degrees, making the growth system uncontrollable, and the deviation of the components will make crystal growth very difficult. Can't even grow crystals

And the lead oxide volatilized during the growth process will pollute the environment and cause harm to the body.

Traditional crucibles for crystal growth are generally hollow cylinders. The bottom of the container and the side wall form an angle of 90 degrees. The convection of the solution tends to produce dead ends here, and the solute and solution here cannot communicate with other parts of the system in a timely manner. exchange, resulting in the inhomogeneity of the system, and the miscellaneous crystals produced here will also change the saturation of the system, which is not conducive to the growth of large-sized and high-quality crystals

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