Preparation method of rare earth silicide monocrystal

Abstract

The invention discloses a preparation method of a rare earth silicide monocrystal. The method comprises the following steps: (I) preparing an EuPd eutectic alloy; (II) weighing palladium particles, silicon blocks and EuPd eutectic alloy at a mass ratio (Eu:Pd:Si) of (33.3+X):(16.7-X):50 to prepare a PdSi binary alloy; (III) uniformly melting the EuPd eutectic alloy and PdSi binary alloy in an induction heater to obtain a melt; and casting the melt into a rod; (IV) cutting the rod to obtain a seed crystal rod and a feed rod; (V) mounting the feed rod on an upper shaft in a crystal growing chamber, mounting the seed crystal rod on a lower shaft, introducing high-purity argon, growing a crystal by a photo-floating zone melting method, and after the crystal growth is over, cooling and taking out the crystal; and (VI) performing linear cutting to obtain the rare earth silicide monocrystal. The method disclosed by the invention can be used for preparing a high-quality rare earth silicide monocrystal with little precipitate and without dislocation or twin crystal.

Description

technical field [0001] The invention belongs to the technical field of crystal growth, and in particular relates to a method for preparing a rare earth silicide single crystal. Background technique [0002] Rare earth silicide single crystal containing volatile element Eu is an important material used in new disk storage and sensors. However, its growth is a difficult point, mainly because Eu element has the characteristics of low melting point, high vapor pressure and crystal matrix. Oriented precipitated phases exist in vivo. [0003] In order to suppress the volatilization of volatile elements during the crystal growth process, researchers at home and abroad have made various attempts, mainly taking three measures: 1) choose a faster growth rate to reduce the volatilization of volatile elements during the crystal growth process. loss, LiFePO was prepared by the suspension zone melting method in the literature "Floating zone growth of lithium iron(II) phosphate single cry...

AI Technical Summary

Problems solved by technology

[0004] It can be seen that increasing the growth rate and reducing the crystal growth time can reduce the loss of volatile elements in the whole process, but if the growth rate is too fast, the supercooling phenomenon of the crystal interface will easily cause the generation of the second phase. The method of high-pressure gas and circulating air flow can effectively suppress the volatilization of some elements (such as Li, Se), but it cannot effectively suppress the elements with high vapor pressure (such as Eu)

Images