Hydrodynamical conditions in the melt at the growth of sapphire and YAG crystals by horizontal directed crystallization

Abstract

Investigated are the hydrodynamical conditions in the melt at the growth of sapphire and yttrium-aluminum garnet (YAG) by the method of horizontal directed crystallization. Specific features of the formation of convective structures depending on the temperature conditions, geometrical parameters of the melt zone and crystal growth stage, are established. It is shown that at the growth of massive (>= 40-50 mm) sapphire and YAG crystals the two-layer structure of the melt flow may be formed at the crystallization front.