METHOD OF SULPHIDE COMPOUND CRYSTAL GROWTH BASED ON RARE-EARTH ELEMENT SESQUIALTERAL SULPHIDES Russian patent published in 2013 - IPC C30B9/02 C30B29/46 

FIELD: metallurgy.

SUBSTANCE: invention relates to production of sulphide compound crystals based on sesquialteral sulphides of rare-earth metals doped with tin, including in the form of high-temperature polymorphous γ-modification. Proposed method comprises loading of initial components into heat-resistant crucible, placing the latter into quartz reactor, degassing and sealing of said reactor and heating the latter in oven. Said initial components represent the mix of sesquialteral sulphide of rare-earth element, REE=Y, La-Lu, and tin sulphide, or mix of powders of sesquialteral sulphide of rare-earth element and tin sulphide, or mix of elementary lanthanide, tin and sulfur taken in stoichiometric ratio for synthesis of Ln₂S₃ and SnS. Reactor is heated to above tin sulphide fusion point, tin sulphide being used as a solvent, and kept at said temperature unless melt-solution homogenising. Then, temperature gradient is developed over the reactor length for solvent mass transfer from said melt-solution into colder part of said reactor, evaporation of solvent and crystallisation from melt-solution with doping of crystals by tin cation.

EFFECT: possibility to grow crystals, larger sizes of grown crystals, expanded range of grown crystals, decreased losses of rare-earth metals in crystallisation.

2 cl, 1 tbl, 4 ex