High-quality BIBO crystal growth method

Abstract

The invention provides a high-quality BIBO crystal growth method. Bismuth oxide and boric acid are adopted as raw materials, a special-shaped crucible is adopted as a growth device, the crucible is made of platinum, and the crucible is in an inverted cone shape; the seed crystal rod is made of platinum, and seed crystals are immersed in the melt and located in the middle of the melt; the crucibleis arranged in the middle of the hearth, and the temperature change range of the position of the hearth crucible is within 1 DEG C. The inverted conical special-shaped crucible is adopted, preferably,small sawteeth are arranged on the inner side face, the included angle between the inclined face of the crucible and the vertical direction is 30-45 degrees, the requirement for downward growth of BIBO crystals is met, convection of melt is enhanced, and uniformity is improved; the influence of external temperature fluctuation on crystal growth is effectively reduced, the uniformity of the melt at the crystal growth part is ensured, and the melt is fully stirred to obtain the BIBO crystal with the optimal crystal quality.

Description

Technical field[0001]The invention relates to the field of artificial crystal growth, in particular to a high-quality BIBO crystal growth method.Background technique[0002]Bismuth borate (BIBO) is a newly developed nonlinear optical crystal. It has the characteristics of large effective nonlinear optical coefficient, high damage threshold and not easy to deliquesce. The nonlinear optical coefficient is about 3.5~4 times that of LBO and 1.5~2 times that of BBO, which is an excellent multiple for producing blue light. Frequency crystal.[0003]The conventional growth method of BIBO crystal adopts the conventional molten salt method to grow, Bi2O3And B2O3As the raw material for growth, the grown crystal is yellowish with an envelope inside the crystal, and the utilization rate is only 30%-50%.[0004]As BIBO crystal raw material Bi2O3With B2O3, The density of the two is very different (Bi2O3Density 9.3 g / cm3, B2O3Density 2.46g / cm3), it is difficult to form a uniform melt, which is detriment...

AI Technical Summary

Problems solved by technology

[0004] Since the BIBO crystal raw material Bi 2 o 3 with B 2 o 3 , the densities of the two are very different (Bi 2 o 3 Density 9.3 g / cm3, B 2 o 3 Density 2.46g / cm3), it is difficult to form a uniform melt, which is not conducive to the formation of crystal growth units, and the viscosity of BIB0 melt is very high, which limits the mass transport during the crystal growth process and hinders the spontaneous formation of crystal nuclei

At the same time, BIBO crystals belong to polar crystals, with prominent polar growth habits. The growth rate at both ends of the polar axis is very different. It is difficult to show the development of crystals in a nearly balanced shape, which is easy to form crystal defects, so BIBO crystals are difficult to grow.

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