METHOD FOR GROWING OF SAPPHIRE SINGLE CRYSTALS FROM MELT Russian patent published in 2009 - IPC C30B17/00 C30B29/20 C30B15/36 

FIELD: physics.

SUBSTANCE: invention is related to the field of single crystals growing from melts and may be used in enterprises of chemical and electronic industry for growing of sapphire single crystals of 1-6 quality category by Kyropulos method from melts on seed crystal. Method includes preparation of charge, its loading and melting by means of heating element in vacuum, seeding and pulling of single crystal, at that growing of single crystal is carried out to seed of technical quality of 6 category, which contains gas inclusions with size of up to 500 mcm and their accumulation, by means of seed crystal lowering by 10 mm every 10-12 minutes until it touches melt with temperature of 2330 K, which has no nucleation centers on the surface, seed crystal submersion for 20-30 sec in melt at 10-15 mm, lowering of heating element power until melt supercooling, which is required for nucleation of crystallisation grains on seed crystal surface in process of constrictions growth, and formation of cone-shaped convex crystallisation front in direction of melt.

EFFECT: growth of sapphire single crystals of optical quality on seed crystal of technical quality with content of gas inclusions and their clusters with diameter of up to 500 mcm, which makes it possible to reduce prime cost of single-crystal sapphire.